Radiation-sensitive resin composition

ABSTRACT

A chemically amplified radiation-sensitive resin composition comprising a specific copolymer and a photoacid generator, wherein the copolymer contains the following recurring unit (1) and/or the recurring unit (2), and the recurring unit (3-1),  
                 
 
wherein R 1  is a hydrogen or methyl, R 2  is a C 4-10  tertiary alkyl, R 3  and R 4  are a hydrogen, C 1-12  alkyl, C 6-15  aromatic, C 1-12  alkoxyl, or R 3  and R 4  may form, in combination and together with the nitrogen atom with which the R 3  and R 4  groups bond, a C 3-15  cyclic structure, provided that R 3  and R 4  are not a hydrogen atom at the same time. The composition effectively responds to various radiations, exhibits excellent resolution and pattern configuration and minimal iso-dense bias, and can form fine patterns at a high precision and in a stable manner.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a radiation-sensitive resin compositionand, more particularly, to a radiation-sensitive resin compositionsuitable as a chemically amplified positive-tone resist and a chemicallyamplified negative-tone resist for ultra-microprocessing using varioustypes of radiation such as ultraviolet radiation, deep ultravioletradiation, X-rays, and charged particle rays.

2. Description of the Background Art

In the field of microfabrication represented by fabrication ofintegrated circuit devices, the design rules have become more and moreminute in order to achieve higher integration. In recent years,development of a lithographic process enabling high accuracymicrofabrication with a line width of 0.3 μm or less in a stable mannerhas been strongly demanded.

However, it is difficult to form such a fine pattern with high accuracyusing a conventional method which utilizes visible rays (wavelength:700-400 nm) or near ultraviolet rays (wavelength: 400-300 nm). To dealwith this problem, a lithographic process using radiation with a shorterwavelength (wavelength: 300 nm or less) which can achieve a wider depthof focus and is effective for ensuring design rules with minimumdimensions has been proposed.

As a lithographic process using radiation with a short wavelength,processes using deep ultraviolet rays such as a KrF excimer laser(wavelength: 248 nm) or an ArF excimer laser (wavelength: 193 nm),X-rays such as synchrotron radiation, and charged particle rays such asultra-deep ultraviolet rays or electron beams have been proposed.International Business Machines Corporation (IBM) has proposed a“chemically-amplified resist” as a resist exhibiting high resolution forsuch short wavelength radiation. At present, improvement of thechemically amplified resist is actively being undertaken.

The chemically-amplified resist contains a photoacid generator whichgenerates an acid upon irradiation (hereinafter called “exposure”).Chemical changes in the resist film (changes in polarity, breakage of achemical bond, cross-linking reaction, etc.) caused by the catalyticaction of an acid changes solubility of the exposed area in a developer.A pattern is formed utilizing this phenomenon.

As such a chemically-amplified resist exhibiting comparatively goodresist performance, a resist comprising a resin in which an alkaliaffinitive group in an alkali-soluble resin is protected by a group suchas a ketal group (Japanese Patent Application Laid-open No. 140666/1995)or an acetal group (Japanese Patent Applications Laid-open No.161436/1990, No. 249682/1993), a resist comprising a copolymercontaining a t-butoxy(α-methyl) styrene unit, hydroxy(α-methyl) styreneunit, and t-butyl (meth)acrylate unit (Japanese Patent ApplicationLaid-open No. 211258/1992), and the like are known.

However, since these chemically-amplified resists have peculiarproblems, various problems in putting these resists to practical use formicrofabrication with a design line width of 0.25 μm or less have beenpointed out.

One serious problem is a change in the resist patterns such as a changein the line width or change into T-character configuration according topost exposure delay (PED), which is a period of time from exposure topost bake.

In recent years, the device structure has become more and morecomplicated. This requires a resist with excellent processingperformance for narrow space (dark field) patterns of which the spacewidth is narrower than an ordinary line width.

Another problem brought about by microprocessing and complication oflithographic processes is an iso-dense bias, which is a criticaldimension (CD) difference between isolated patterns and dense patterns.

An object of the present invention is to provide a radiation-sensitiveresin composition useful as a positive-tone or negative-tone chemicallyamplified resist, effectively responding to various radiations,exhibiting excellent resolution and pattern configuration, the patternconfiguration and line width being affected by PED to a minimal extent,particularly excelling in narrow space processing performance, a minimaliso-dense bias, CD uniformity in various pattern designs, and capable offorming fine patterns at a high precision and in a stable manner.

SUMMARY OF THE INVENTION

According to the present invention, the above object can be achieved bya positive-tone radiation-sensitive resin composition comprising (A1) acopolymer which comprises a recurring unit shown by the followingformula (1) and/or a recurring unit shown by the following formula (2),and a recurring unit shown by the following formula (3-1), and (B) aphotoacid generator,

wherein R¹ represents a hydrogen atom or a methyl group;

wherein R¹ represents a hydrogen atom or a methyl group, and R²represents a tertiary alkyl group having 4-10 carbon atoms;

wherein R¹ represents a hydrogen atom or a methyl group, R³ and R⁴individually represent a hydrogen atom, a substituted or unsubstitutedalkyl group having 1-12 carbon atoms, a substituted or unsubstitutedaromatic group having 6-15 carbon atoms, or a substituted orunsubstituted alkoxyl group having 1-12 carbon atoms, or R³ and R⁴ mayform, in combination and together with the nitrogen atom with which theR³ and R⁴ groups bond, a cyclic structure having 3-15 carbon atoms,provided that R³ and R⁴ are not a hydrogen atom at the same time.

The above object can also be achieved in the present invention by anegative-tone radiation-sensitive resin composition comprising (A2) acopolymer which comprises a recurring unit shown by the above formula(1) and a recurring unit shown by the above formula (3-1), (B) aphotoacid generator, and (C) a compound which can cross-link thecopolymer (A1) in the presence of an acid.

The above object can further be achieved in the present invention by aradiation-sensitive resin composition comprising (A3-1) a resincomprising a recurring unit shown by the following formula (3-2), whichis insoluble or scarcely soluble in alkali and becomes alkali soluble bythe action of an acid, and (B) a photoacid generator,

R^(3′) and R^(4′) individually represent a hydrogen atom, a substitutedor unsubstituted alkyl group having 1-12 carbon atoms, a substituted orunsubstituted alkoxyl group having 1-12 carbon atoms, or a substitutedor unsubstituted alkoxycarbonyl group having 2-13 carbon atoms, orR^(3′) and R^(4′) may form, in combination and together with thenitrogen atom with which the R^(3′) and R^(4′) groups bond, a cyclicstructure having 3-15 carbon atoms, and n is an integer of 0-3.

The above object can still further be achieved in the present inventionby a radiation-sensitive resin composition comprising (A3-2) a resincomprising a recurring unit shown by the following formula (3-1′) and analicyclic skeleton, which is insoluble or scarcely soluble in alkali andbecomes alkali soluble by the action of an acid, and (B) a photoacidgenerator,

wherein R¹ represents a hydrogen atom or a methyl group, R^(3″) andR^(4″) individually represent a hydrogen atom, a substituted orunsubstituted alkyl group having 1-12 carbon atoms, a substituted orunsubstituted alkoxyl group having 1-12 carbon atoms, or a substitutedor unsubstituted alkoxycarbonyl group having 2-13 carbon atoms, orR^(3″) and R^(4″) may form, in combination and together with thenitrogen atom with which the R^(3″) and R^(4′)″ groups bond, a cyclicstructure having 3-10 carbon atoms.

The component (A3-1) and component (A3-2) may be hereinafter referred toas the component (A3).

Other objects, features and advantages of the invention will hereinafterbecome more readily apparent from the following description.

DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS

The present invention will be described in detail below.

Component (A1)

The component (A1) in the positive-tone radiation-sensitive resincomposition of the present invention is a copolymer containing eitherone or both of a recurring unit shown by the above formula (1)(hereinafter referred to as “recurring unit (1)”) and a recurring unitshown by the above formula (2) (hereinafter called “recurring unit (2)”)and a recurring unit shown by the above formula (3-1) (hereinafterreferred to as “recurring unit (3-1)”). Such a copolymer is hereinafterreferred to as “copolymer (A1).”

In the resin (A1), each recurring unit (1), (2), and (3) may be usedeither individually or in combination of two or more, respectively.

When the copolymer (A1) contains only either one of the recurring unit(1) or the recurring unit (2), it is desirable to use other (co)polymerscontaining either the recurring unit (1) or the recurring unit (2) orboth, so that the copolymer components in the positive-tone radiationsensitive composition of the present invention may, as a whole, containall of the recurring unit (1), recurring unit (2), and recurring unit(3-1). The copolymer (A1) and the other (co)polymers may hereinafter bereferred to collectively as “copolymer component (A1)”.

The following combinations (1) to (3) of the copolymers can be given asparticularly preferred specific examples of the present invention:

(1) a copolymer (A1) containing the recurring unit (1), recurring unit(2), and recurring unit (3-1),

(2) combination of a copolymer (A1) containing the recurring unit (1)and recurring unit (3-1) and another copolymer containing the recurringunit (1) and recurring unit (2), and

(3) combination of a copolymer (A1) containing the recurring unit (2)and recurring unit (3-1) and another copolymer containing the recurringunit (1) and recurring unit (2).

The content of the recurring unit (1) in all copolymers in the positivetone radiation sensitive composition is 20-90 mol %, preferably 30-85mol %, and still more preferably 40-80 mol % of the total amount of therecurring units (1), (2), and (3-1). If the content of the recurringunit (1) is too small, sensitivity as a resist tends to decrease. If thecontent is too large, the resulting pattern shape may be impaired.

The amount of the recurring unit (2) is usually 5-50 mol %, preferably5-30 mol % of the total amount of the recurring units (1), (2), and(3-1). If the content of the recurring unit (2) is too small, patternresolution as a resist tends to decrease. If the content is too large,environmental resistance may be impaired.

The amount of the recurring unit (3-1) is usually 0.01-30 mol %,preferably 0.1-20 mol % of the total amount of the recurring units (1),(2), and (3-1). If the content of the recurring unit (3-1) is too small,iso-dense bias as a resist tends to be impaired. If the content is toolarge, solubility in solvents tends to decrease.

Recurring Unit (1)

As examples of preferable monomers which provide the recurring unit (1)in the copolymer (A1), o-hydroxystyrene, m-hydroxystyrene,p-hydroxystyrene, o-hydroxy-α-methylstyrene, m-hydroxy-α-methylstyrene,p-hydroxy-α-methylstyrene, and the like can be given. These monomers maybe used either individually or in combination of two or more.

Recurring Unit (2)

As examples of the tertiary alkyl group having 4-10 carbon atomsrepresented by R² in the recurring unit (2), a t-butyl group,1,1-dimethylpropyl group, 1,1-dimethylbutyl group, 1,1-dimethylpentylgroup, 1,1-dimethylhexyl group, 1,1-dimethylheptyl group,1,1-dimethyloctyl group, 1-methyl-1-ethylpropyl group,1-methyl-1-ethylbutyl group, 1-methyl-1-ethylpentyl group,1-methyl-1-ethylhexyl group, 1-methyl-1-ethylheptyl, methylcyclohexylgroup, 1-ethylcyclohexyl group, 1-methylcyclopentyl group,1-ethylcyclopentyl group, 1-benzylisobutanyl group,2-norbornaneisobutanyl group, methyladamantyl group, and the like can begiven.

As examples of preferable monomers which provide the recurring unit (2),a p-t-butoxystyrene, p-1,1-dimethylpropoxystyrene,p-1,1-dimethylbutoxystyrene, p-1,1-dimethylpentyloxystyrene,1,1-dimethylhexyloxystyrene, p-1,1-dimethylheptyloxystyrene,p-1,1-dimethyloctyloxystyrene, p-(2-phenyl-2-propyloxy)styrene,p-t-butoxy-α-methylstyrene, p-1,1-dimethylpropoxy-α-methylstyrene,p-1,1-dimethylbutoxy-α-methylstyrene,p-1,1-dimethylpentyloxy-α-methylstyrene,p-1,1-dimethylhexyloxy-α-methylstyrene,p-1,1-dimethylheptyloxy-α-methylstyrene,p-1,1-dimethyloctyloxy-α-methylstyrene, methylcyclohexyloxystyrene,1-ethylcyclohexyloxystyrene, 1-methylcyclopentyloxystyrene,1-ethylcyclopentyloxystyrene, 1-benzylisobutanyloxystyrene and2-norbornaneisobutanyloxystyrene, methyladamantyloxystyrene, and thelike can be given. These monomers may be used either individually or incombination of two or more.

Recurring Unit (3-1)

Given as examples of alkyl groups having 1-12 carbon atoms representedby R³ or R⁴ in the recurring unit (3-1) are linear, branched, or cyclicalkyl groups such as a methyl group, ethyl group, n-propyl group,i-propyl group, n-butyl group, 2-methylpropyl group, 1-methylpropylgroup, t-butyl group, n-pentyl group, neopentyl group, n-hexyl group,cyclopentyl group, and cyclohexyl group; linear, branched, or cyclichydroxyalkyl groups such as a hydroxymethyl group, 2-hydroxyethyl group,3-hydroxypropyl group, 4-hydroxybutyl group, 3-hydroxycyclopentyl group,and 4-hydroxycyclohexyl group; linear, branched, or cyclic alkoxyalkylgroups such as a methoxymethyl group, ethoxymethyl group, i-butoxymethylgroup, 2-methoxyethyl group, 2-ethoxyethyl group, 3-methoxypropyl group,3-ethoxypropyl group, 4-methoxybutyl group, 4-ethoxybutyl group,3-methoxycyclopentyl group, 3-ethoxycyclopentyl group,4-methoxycyclohexyl group, and 4-ethoxycyclohexyl group; linear,branched, or cyclic carboxyalkyl groups such as a carboxymethyl group,2-carboxyethyl group, 3-carboxypropyl group, 4-carboxybutyl group,3-carboxycyclopentyl group, and 4-carboxycyclohexyl group; and linear,branched, or cyclic cyanoalkyl groups such as a cyanomethyl group,2-cyanoethyl group, 3-cyanopropyl group, 4-cyanobutyl group,3-cyanocyclopentyl group, and 4-cyanocyclohexyl group.

As examples of substituted or unsubstituted aromatic groups having 6-15carbon atoms, a phenyl group, benzyl group, tosyl group, and ansyl groupcan be given.

The following groups can be given as examples of substituted orunsubstituted alkoxyl groups having 1-12 carbon atoms represented by R³or R⁴: linear, branched, or cyclic alkoxyl groups such as a methoxygroup, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group,2-methylpropoxy group, 1-methylpropoxy group, t-butoxy group,n-pentyloxy group, n-hexyloxy group, and cyclopentyloxy group, andcyclohexyloxy group; linear, branched, or cyclic hydroxyalkoxyl groupssuch as hydroxymethoxy group, 2-hydroxyethoxy group, 3-hydroxypropoxygroup, 4-hydroxybutoxy group, 3-hydroxycyclopentyloxy group, and4-hydroxycyclohexyloxy group; linear, branched, or cyclic alkoxyalkoxylgroups such as methoxymethoxy group, ethoxymethoxy group,2-methoxyethoxy group, 2-ethoxyethoxy group, 3-methoxypropoxy group,3-ethoxypropoxy group, 4-methoxybutoxy group, 4-ethoxybutoxy group,3-methoxycyclopentyloxy group, 3-ethoxycyclopentyloxy group,4-methoxycyclohexyloxy group, and 4-ethoxycyclohexyloxy group; linear,branched, or cyclic carboxyalkoxyl groups such as carboxymethoxy group,2-carboxyethoxy group, 3-carboxypropoxy group, 4-carboxybutoxy group,3-carboxycyclopentyloxy group, and 4-carboxycyclohexyloxy group; andlinear, branched, or cyclic cyanoalkoxyl groups such as cyanomethoxygroup, 2-cyanoethoxy group, 3-cyanopropoxy group, 4-cyanobutoxy group,3-cyanocyclopentyloxy group, and 4-cyanocyclohexyloxy group.

The cyclic structure having 3-15 carbon atoms, formed by the groups R³and R⁴ and the nitrogen atom with which the R³ and R⁴ groups bond, mayfurther contain one or more types of hetero atoms such as an oxygen atomor nitrogen atom, in addition to the nitrogen atom with which the R³ andR⁴ groups bond.

Given as examples of such a cyclic structure, in terms of the cyclicstructural group containing the nitrogen atom with which the R³ and R⁴groups bond, are 1-pyrrolidinyl group, 1-pyrrolyl group, 2-pyrrolin-1-ylgroup and 3-pyrrolin-1-yl group, indolyl group, 2-iso-indolyl group,1-imidazolyl group, 1-benzoimidazolyl group, 2-phenylimidazolyl group,2-phenyl-1-benzoimidazolyl group, 2-imidazolin-1-yl group,3-imidazolin-1-yl group, 1-pyrazolyl group, indazolyl group, 1-indolinylgroup, 2-isoindolinyl group, 7-purinyl group, 9-carbazolyl group,1-perimidinyl group, 10-phenothiazinyl group, 10-phenoxazinyl group,1-piperidino group, and morpholino group.

The above-mentioned cyclic structure may contain one or moresubstituents of the types previously given as examples of substitutentsfor alkyl groups, such as a hydroxyl group alkoxyl group, carboxylgroup, and cyano group.

Examples of monomers providing the recurring unit (3) include(meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide,N-cyclohexyl(meth)acrylamide, N-hydroxymethyl(meth)acrylamide,N-hydroxyethyl(meth)acrylamide, N-iso-butoxyethyl(meth)acrylamide,N-phenyl(meth)acrylamide, N-benzyl(meth)acrylamide,N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide,N,N-dicyclohexyl(meth)acrylamide, N,N-dihydroxyethyl(meth)acrylamide,N,N-diphenyl(meth)acrylamide, N,N-dibutyl(meth)acrylamide,N,N′-methylene-bis(acrylamide), 1-(meth)acryloyl pyrrolidine,1-(meth)acryloyl pyrroline, 1-(meth)acryloyl(2-pyrroline),1-(meth)acryloyl(3-pyrroline), 1-(meth)acryloyl indole, 2-(meth)acryloyliso-indole, 1-(meth)acryloyl imidazole, 1-(meth)acryloyl benzimidazole,1-(meth)acryloyl-2-phenylimidazole,1-(meth)acryloyl-2-phenylbenzimidazole, 1-(meth)acryloyl-2-imidazole,1-(meth)acryloyl-3-imidazole, 1-(meth)acryloyl pyrazoline,1-(meth)acryloyl indazole, 1-(meth)acryloyl indoline, 2(meth)acryloyliso-indole, N-(meth)acryloyl carbazole, 7-(meth)acryloyl purine,9-(meth)acryloyl carbazole, 1-(meth)acryloyl perimidine,10-(meth)acryloyl phenothiazine, 10-(meth)acryloyl phenoxazine,1-(meth)acryloyl piperidine, 1-(meth)acryloyl morpholine,N-(meth)acryloyl piperazine, N-(meth)acryloyl piperidine,N-(meth)acryloyl pyrazoline, N-(meth)acryloyl triazole, 7-(meth)acryloyladenine, 7-(meth)acryloyl quanine, 1-(meth)acryloyl thymine,1-(meth)acryloyl cytosine, and 1-(meth)acryloyl uracil. These monomersmay be used either individually or in combinations of two or more.

Other Recurring Units

The copolymer (A1) and the above-mentioned other copolymers may compriseone or more recurring units other than the recurring units (1), (2), and(3-1) (hereinafter referred to as other recurring units {circle over(1)}″).

The following compounds can be given as examples of monomers providingsuch other recurring units {circle over (1)}: styrenes such as styrene,α-methylstyrene, o-methoxystyrene, m-methoxystyrene, andp-methoxystyrene; unsaturated carboxylic acids and acid anhydridiesthereof such as (meth)acrylic acid, maleic acid, fumaric acid, crotonicacid, mesaconic acid, citraconic acid, and itaconic acid, maleicanhydride, and methylmaleic anhydride; esters of the above unsaturatedcarboxylic acids, such as methyl ester, ethyl ester, n-propyl ester,i-propyl ester, n-butyl ester, t-butyl ester, i-butyl ester, sec-butylester, n-amyl ester, 2-hydroxyethyl ester, 2,2-dimethyl-3-hydroxypropylester, benzyl ester, 1-methyl-1-ethylpropylmethyl ester,1-methyl-1-ethylbutylmethyl ester, 1-methyl-1-ethylpentylmethyl ester,1-methyl-1-ethylhexylmethyl ester, 1-methyl-1-ethylheptyl,methylcyclohexylmethyl ester, 1-ethylcyclohexylmethyl ester,1-methylcyclopentylmethyl ester, 1-ethylcyclopentylmethyl ester,1-benzylisobutanylmethyl ester, 2-norbornaneisobutanylmethyl ester, andmethyladamantylmethyl ester; unsaturated nitrile compounds such as(meth)acrylonitrile, maleinitrile, fumaronitrile, mesaconitrile,citraconitrile, and itaconitrile; unsaturated amide compounds such as(meth)acrylamide, crotonamide, maleinamide, fumaramide, mesaconamide,citraconamide, and itaconamide; unsaturated imides such as maleimide andN-phenylmaleimide; unsaturated alcohols such as (meth)allylalcohol;vinyl anilines; vinyl pyridines; and other vinyl compounds such asN-vinyl-ε-caprolactam, N-vinylpyrrolidone, N-vinylimidazole, andN-vinylcarbazole.

These monomers may be used either individually or in combinations of twoor more.

The content of the other recurring units {circle over (1)} in thecopolymer components (A1) is usually 30 wt % or less of the total amountof the recurring units (1), (2), and (3-1).

The polystyrene-reduced weight average molecular weight (hereinafterreferred to as “Mw”) of the copolymer (A1) determined by gel permeationchromatography (hereinafter referred to as “GPC”) is 1,000-100,000,preferably 3,000-40,000, and still more preferably 3,000-30,000. If Mwof the copolymer (A1) is less than 1,000, sensitivity and heatresistance as a resist tend to decrease. If Mw exceeds 100,000,solubility in a developer tends to decrease.

In the copolymer (A1), the ratio of Mw to Mn (polystyrene-reduced numberaverage molecular weight determined by GPC) (Mw/Mn) is 1.0-5.0, andpreferably 1.0-3.0. The Mw and the ratio of Mw to Mn of the copolymer(A1) apply to the other copolymers.

The copolymer (A1) is prepared using the following methods, for example.

(a) A method of copolymerizing a hydroxy(α-methyl)styrene with a monomercorresponding to the recurring unit (2) and a monomer corresponding tothe recurring unit (3-1).

(b) A method of copolymerizing an acetoxy(α-methyl)styrene with amonomer corresponding to the recurring unit (2) and a monomercorresponding to the recurring unit (3-1), followed by hydrolysis and/orsolvolysis of acetoxy groups in the copolymer using a basic catalyst.

(c) A method of copolymerizing a monomer corresponding to the recurringunit (2) and a monomer corresponding to the recurring unit (3-1),followed by hydrolysis and/or solvolysis of —OR² groups in the copolymerusing an acidic catalyst.

The copolymerization by the methods (a) to (c) above is carried out byblock polymerization, solution polymerization, precipitationpolymerization, emulsion polymerization, suspension polymerization,block-suspension polymerization, and the like using an appropriatepolymerization initiator such as a radical polymerization initiator oranionic polymerization initiator.

If necessary, the copolymer (A1) can be blended with a resin or a lowmolecular weight compound having good mutual solubility with thecopolymer (A1) and not impairing homogeneity of the coating film whenthe composition is applied to a substrate.

Component (A-2)

The component (A2) in the negative tone radiation sensitive compositionof the present invention is a copolymer comprising the recurring unit(1) and the recurring unit (3-1) (hereinafter referred to as “copolymer(A2)”).

In the copolymer (A2), each of the recurring unit (1) and (3-1) may beused either individually or in combinations of two or more,respectively.

The copolymer (A2) may be used together with other (co)polymers in thenegative tone radiation sensitive composition of the present invention.In addition, the copolymer (A2) may comprise recurring units other thanthe recurring unit (1) and the recurring unit (3-1) (the copolymer (A2)and other (co)polymers may hereinafter be collectively referred to as“copolymer component (A2)”).

The content of the recurring unit (3-1) in the copolymer component (A2)of the negative tone radiation sensitive composition is usually 0.1-30mol %, preferably 0.1-15 mol %, and still more preferably 0.1-10 mol %of the total amount of the recurring unit (1) and the recurring unit(3-1). If the content of the recurring unit (1) is to small, improvementin the iso-dense bias may be insufficient; if the content is too large,sensitivity tends to decrease.

The monomers used for the copolymer (A1) can be preferably used as themonomers providing the recurring unit (1) and the recurring unit (3-1).

The copolymer (A2) and the above-mentioned other copolymers mayoptionally comprise the recurring unit (2) and the other recurring units{circle over (1)}. The content of the recurring unit (2) and the otherrecurring units {circle over (1)} in the copolymer component (A2) of thenegative tone radiation sensitive composition is 50 wt % or less, andpreferably 30 wt % or less, of the total amount of the recurring units(1) and (3-1).

Mw of the copolymer (A2) is usually 500-100,000, preferably1,000-50,000, and still more preferably 1,000-30,000. If Mw of thecopolymer (A2) is less than 500, sensitivity and heat resistance as aresist tend to decrease. If Mw exceeds 100,000, solubility in adeveloper tends to decrease.

Mw/Mn of the copolymer (A2) is 1.0-3.0, and preferably 1.0-2.0.

The copolymer (A2) is prepared using the following methods, for example.

(a′) A method of copolymerizing a hydroxy(α-methyl)styrene with amonomer corresponding to the recurring unit (3-1).

(b′) A method of copolymerizing an acetoxy(α-methyl)styrene with amonomer corresponding to the recurring unit (3-1), followed byhydrolysis and/or solvolysis of acetoxy groups in the copolymer using abasic catalyst.

(c′) A method of copolymerizing a monomer corresponding to the recurringunit (2) and a monomer corresponding to the recurring unit (3-1),followed by hydrolysis and/or solvolysis of —OR² groups in the copolymerusing a basic catalyst.

The copolymerization in the methods (a′) to (c′) is carried out by blockpolymerization, solution polymerization, precipitation polymerization,emulsion polymerization, suspension polymerization, block-suspensionpolymerization, and the like using an appropriate radical polymerizationinitiator.

If necessary, the copolymer (A2) can be blended with an alkali solubleresin or a low molecular weight compound having good mutual solubilitywith the copolymer (A2) and not impairing homogeneity of the coatingfilm when the composition is applied to a substrate.

Component (A3)

The component (A3) of the present invention is a resin comprising arecurring unit shown by the formula (3-2) (hereinafter referred to as“recurring unit (3-2)”), insoluble or scarcely soluble in alkali andbecoming alkali soluble by the action of an acid (hereinafter referredto as “resin (A3-1)”) or a resin comprising a recurring unit shown bythe formula (3-1′) (hereinafter referred to as “recurring unit (3-1′)”)and an alicyclic structure, insoluble or scarcely soluble in alkali andbecoming alkali soluble by the action of an acid (hereinafter referredto as “resin (A3-2)”).

The resin (A3-1) or resin (A3-2) provides the radiation-sensitive resincomposition of the present invention exhibiting superior transparency toradioactive rays, particularly to an ArF excimer laser, and exhibitingonly a slight line width fluctuation due to an increase or decrease of aspace width when the composition is used as a resist.

As groups represented by R^(3′) or R^(4′) in the formula (3-2), inaddition to the groups previously mentioned as the groups represented byR³ or R⁴, the following substituted or unsubstituted alkoxycarbonylgroups having 2-13 carbon atoms can be given: a linear, branched, orcyclic alkoxycarbonyl groups such as a methoxycarbonyl group,ethoxycarbonyl group, n-propoxycarbonyl group, i-propoxycarbonyl group,n-butoxycarbonyl group, 2-methylpropoxycarbonyl group,1-methylpropoxycarbonyl group, t-butoxycarbonyl group,n-pentyloxycarbonyl group, n-hexyloxycarbonyl group,cyclopentyloxycarbonyl group, and cyclohexyloxy carbonyl group; linear,branched, or cyclic hydroxyalkoxycarbonyloxy groups such as ahydroxymethoxycarbonyl group, 2-hydroxyethoxycarbonyl group,3-hydroxypropoxycarbonyl group, 4-hydroxybutoxycarbonyl group,3-hydroxycyclopentyloxycarbonyl group, and4-hydroxycyclohexyloxycarbonyl group; alkoxyalkoxycarbonyl groups suchas a methoxymethoxycarbonyl group, ethoxyethoxycarbonyl group,2-methoxyethoxycarbonyl group, 2-ethoxyethoxycarbonyl group,3-methoxypropoxycarbonyl group, 3-ethoxypropoxycarbonyl group,4-methoxybutoxycarbonyl group, 4-ethoxybutoxycarbonyl group,3-methoxycyclopentyloxycarbonyl group, 3-ethoxycyclopentyloxycarbonylgroup, 4-methoxycyclohexyloxycarbonyl group, and4-ethoxycyclohexyloxycarbonyl group; linear, branched, or cycliccarboxyalkoxycarbonyloxy groups such as a carboxymethoxycarbonyl group,2-carboxyethoxycarbonyl group, 3-carboxypropoxycarbonyl group,4-carboxybutoxycarbonyl group, 3-carboxycyclopentyloxycarbonyl group,and 4-carboxycyclohexyloxycarbonyl group; and linear, branched, orcyclic cyanoalkoxycarbonyloxy groups such as a cyanomethoxycarbonylgroup, 2-cyanoethoxycarbonyl group, 3-cyanopropoxycarbonyl group,4-cyanobutoxycarbonyl group, 3-cyanocyclopentyloxycarbonyl group, and4-cyanocyclohexyloxycarbonyl group.

As an integer n in the formula (3-2), either 0 or 1 is particularlypreferable.

As examples of monomers which provide the recurring unit (3-2),norbornene derivatives shown by the following formula (I) (hereinaftercalled “norbornene derivatives (I)”) can be given:

wherein R^(3′), R^(4′) and n have the same meanings as defined for thecorresponding symbols in the formula (3-2).

Examples of preferable norbornene derivatives (I) include:bicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide;

-   bicyclo[2.2.1]hept-2-ene derivatives such as,-   N-methylbicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,-   N,N-dimethylbicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,-   N-ethylbicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,-   N,N-diethylbicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,-   N-methoxybicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,-   N,N-dimethoxybicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,    N-ethoxybicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,    N,N-diethoxybicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,-   N-methoxycarbonylbicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,-   N,N-di(methoxycarbonyl)bicyclo[2.2.1]hept-2-ene-5-carboxylic acid    amide,-   N-ethoxycarbonylbicyclo[2.2.1]hept-2-ene-5-carboxylic acid amide,-   N,N-di(ethoxycarbonyl)bicyclo[2.2.1]hept-2-ene-5-carboxylic acid    amide, and bicyclo[2.2.1]hept-2-ene-5-carboxylic acid pyrrolidinyl,    compounds represented by the following formula (I-1), (I-2), or    (I-3),-   tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene derivatives such as    tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic acid    amide,-   N-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N,N-dimethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N,N-diethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N-methoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N,N-dimethoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N-ethoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide, and-   N,N-diethoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N-methoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N,N-di(methoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N-ethoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide,-   N,N-di(ethoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic    acid amide, and-   compounds represented by the following formula (I-4), (I-5), or    (I-6),

Of the above norbornene derivatives (I), bicyclo[2.2.1]hept-2-enecarboxylic acid amide, N,N-dimethylbicyclo[2.2.1]hept-2-ene carboxylicacid amide, N,N-diethylbicyclo[2.2.1]hept-2-ene carboxylic acid amide,the compound of the above formula (I-2), the compound of the aboveformula (I-3),tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylic acid amide,N,N-dimethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylicacid amide,N,N-diethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene-8-carboxylicacid amide, the compound of the above formula (I-5), the compound of theabove formula (I-6), and the like are preferably used.

In the present invention, the norbornene derivatives (I) can be usedeither individually or in combination of two or more.

The groups given for R^(3′) and R^(4′) in the formula (3-2) can be givenas examples of the groups represented by R^(3″) and R^(4″) in theformula (3-1′), which include a substituted or unsubstituted alkyl grouphaving 1-12 carbon atoms, a substituted or unsubstituted alkoxyl grouphaving 1-12 carbon atoms, and a substituted or unsubstitutedalkoxycarbonyl group having 2-13 carbon atoms, as well as a cyclicstructure having 3-15 carbon atoms formed by R^(3″) and R^(4″) togetherwith the nitrogen atom with which the R^(3″) and R^(4″) groups bond.

Particularly preferable groups for R^(3″) and R^(4″) in the formula(3-1′) are a hydrogen atom, methyl group, ethyl group, 2-hydroxyethylgroup, and the like.

As the group R¹ in the formula (3-1′), both the hydrogen atom and methylgroup are preferable.

As examples of monomers which provide the recurring unit (3-1′),monomers previously given in connection with the recurring unit (3-1)(hereinafter referred to from time to time as “(meth)acrylic acidderivatives (II)”) can be given.

Of these monomers, (meth)acrylamide, N,N-dimethyl(meth)acrylamide,(meth)acryloylmorpholine, and the like are preferable.

In the present invention, the above monomers can be used eitherindividually or in combination of two or more.

It is essential that the resin (A3-2) contain an alicyclic skeleton inthe main chain and/or side chain of the molecule.

In addition, it is desirable that the resin (A3-1) and resin (A3-2)contain acid-dissociating group-containing recurring units other thanrecurring units (3-2) and (3-1′), which dissociate in the presence of anacid to form an acidic functional group, such as carboxyl group orsulfonic acid group, in the resin.

As a preferable resin (A3-1) or (A3-2) of the present invention, a resininsoluble or scarcely soluble in alkali containing the recurring unit(3-2) and/or recurring unit (3-1′), and the recurring unit (i) and/orrecurring unit (ii), shown by the following formulas, and becomingalkali soluble by the action of an acid can be given (such a resin ishereinafter referred to as “resin (α)”). A resin containing therecurring unit (3-2) and/or recurring unit (3-1′) and the recurring unit(i) (hereinafter referred to as “resin (α1)”) and a resin containing therecurring unit (3-2) and/or recurring unit (3-1′) and the recurring unitrecurring unit (ii) (hereinafter referred to as “resin (α2)”) areparticularly preferable, provided that the resin (α) and resin (α2) musthave an alicyclic skeleton in the main chain and/or side chain whenthese resins do not have the recurring unit (3-2) or recurring unit (i).

wherein R¹, R^(3′), R^(4′), R^(3″), and R^(4″) are the same as definedfor the above; R⁵ individually represents a linear or branched alkylgroup having 1-4 carbon atoms or a monovalent alicyclic hydrocarbongroup having 4-20 carbon atoms or derivatives thereof, provided that atleast one R⁵ is a linear or branched alkyl group having 1-4 carbonatoms, or any two R⁵ groups form, in combination and together with thecarbon atoms to which the two R⁵groups bond, a divalent alicyclichydrocarbon group having 4-20 carbon atoms or derivatives thereof, withthe remaining R⁵ groups being a linear or branched alkyl group having1-4 carbon atoms; R⁶ individually represents a linear or branched alkylgroup having 1-4 carbon atoms or a monovalent alicyclic hydrocarbongroup having 4-20 carbon atoms or derivatives thereof, provided that atleast one R⁶ is a linear or branched alkyl group having 1-4 carbonatoms, or any two R⁶ groups form, in combination and together with thecarbon atoms to which the two R⁶ groups bond, a divalent alicyclichydrocarbon group having 4-20 carbon atoms or derivatives thereof, withthe remaining R⁵ groups being a linear or branched alkyl group having1-4 carbon atoms; and m and n are an integer of 0-3.

As examples of the linear or branched alkyl group having 1-4 carbonatoms represented by R⁵ or R⁶, a methyl group, ethyl group, n-propylgroup, i-propyl group, n-butyl group, 2-methylpropyl group,1-methylpropyl group, and t-butyl group can be given.

Of these alkyl groups, a methyl group and ethyl group are particularlypreferable.

As examples of the monovalent alicyclic hydrocarbon group having 4-20carbon atoms represented by R⁵ or R⁶, and the divalent alicyclichydrocarbon group having 4-20 carbon atoms formed by R⁵ or R⁶, alicyclicgroups derived from a cycloalkane such as norbornane, tricyclodecane,tetracyclododecane, adamantane, cyclobutane, cyclopentane, cyclohexane,cycloheptane, or cyclooctane, and groups obtained by replacing hydrogenatoms on these alicyclic groups with one or more linear, branched, orunbranched alkyl groups having 1-8 carbon atoms, such as methyl group,ethyl group, n-propyl group, i-propyl group, n-butyl group, 2-methylpropyl group, 1-methyl propyl group, or t-butyl group, can be given.

Of these monovalent and divalent alicyclic hydrocarbon groups, groupscontaining an alicyclic ring derived from norbornane, tricyclodecane,tetracyclododecane, adamantane, cyclopentane, or cyclohexane, or groupsin which these alicyclic ring-containing groups are substituted with theabove alkyl groups are preferable.

As examples of derivatives of the monovalent or divalent alicyclichydrocarbon groups, groups having one or more substitutes, such as ahydroxyl group; a carboxyl group; a linear or branched hydroxyalkylgroup having 1-4 carbon atoms such as a hydroxymethyl group,2-hydroxyethyl group, 3-hydroxypropyl group, and 4-hydroxypropyl group;a linear or branched alkoxyl group having 1-4 carbon atoms such as amethoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxygroup, 2-methylpropoxy group, 1-methylpropoxy group, and t-butoxy group;a cyano group; a linear or branched cyanoalkyl group having 2-5 carbonatoms such as a cyanomethyl group, 2-cyanoethyl group, 3-cyanopropylgroup, and 4-cyanobutyl group; and the like, can be given.

Of these substituents, a hydroxyl group, carboxyl group, hydroxymethylgroup, cyano group, and the like are preferable.

In the resin (α), both the group —COO(R⁵)₃ possessed by the recurringunit (i) and the group —COO(R⁶)₃ possessed by the recurring unit (ii)dissociate in the presence of an acid and produce a carboxyl group.These groups —COO(R⁵)₃ and —COO(R⁶)₃ are hereinafter collectivelyreferred to as “acid-dissociating groups (i).”

As specific preferable examples of the acid-dissociating groups (i),t-butoxycarbonyl group and groups shown by the following formulas (i-1)to (i-47) can be given.

Of these acid-dissociating organic groups (i), t-butoxycarbonyl groupand the groups shown by the formulas (i-1), (i-2), (i-10), (i-11),(i-13), (i-14), (i-16), (i-17), (i-34), (i-35), (i-40), (i-41), (i-46),or (i-47) are particularly preferable.

A particularly preferable integer for m in the recurring units (i) is 0or 1. As the group R¹ in the recurring unit (ii), both the hydrogen atomand methyl group are preferable.

As examples of monomers which provide the recurring unit (i), compoundsshown by the following formula (i′) (hereinafter referred to as“norbornene derivatives (i′)”) can be given:

wherein R⁵ and m are the same as defined for the above formula (i).

Examples of preferable norbornene derivatives (i′) include: compoundshaving an acid-dissociating organic group (i) selected from the groupconsisting of t-butoxycarbonyl group and the groups shown by theformulas (i-1), (i-2), (i-10), (i-11), (i-13), (i-14), (i-16), (i-17),(i-34), (i-35), (i-40), (i-41), (i-46), or (i-47), and having m−0 in theformula (i′); and compounds having an acid-dissociating organic group(i) selected from the group consisting of t-butoxycarbonyl group and thegroups shown by the formulas (i-1), (i-2), (i-10), (i-11), (i-13),(i-14), (i-16), (i-17), (i-34), (i-35), (i-40), (i-41), (i-46), or(i-47), and having m−1 in the formula (i′).

The monomer providing the recurring unit (ii) is a compound derived from(meth)acrylic acid by converting the carboxyl group into theacid-dissociating group (i) (such a compound is hereinafter referred toas “(meth)acrylic acid derivatives (ii′)”).

Compounds having an acid-dissociating group (i) selected from the groupconsisting of t-butoxycarbonyl group and the groups shown by theformulas (i-1), (i-2), (i-10), (i-11), (i-13), (i-14), (i-16), (i-17),(i-34), (i-35), (i-40), (i-41), (i-46), or (i-47) can be given aspreferable (meth)acrylic acid derivatives (ii′) in the presentinvention.

The resin (A3) may comprise at least one recurring unit other than therecurring units (3-2), (3-1′), (i), and (ii) (hereinafter referred to as“other recurring unit {circle over (3)}”).

The following compounds can be given as examples of monomers providingsuch other recurring units {circle over (3)}:

-   mono-functional monomers, which include:-   bicyclo[2.2.1]hept-2-ene derivatives having an acid-dissociating    group which dissociates in the presence of an acid and forms a    carboxyl group in the resin such as-   5-methoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-ethoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-n-propoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-i-propoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-n-butoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-(2-methylpropoxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-(1-methylpropoxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-cyclohexyloxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-(4-t-butylcyclohexyloxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-phenoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-(1-ethoxyethoxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-(1-cyclohexyloxyethoxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-t-butoxycarbonylmethoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-tetrahydrofuranyloxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-tetrahydropyranyloxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-methoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-ethoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-n-propoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-i-propoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-n-butoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-(2-methylpropoxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-(1-methylpropoxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-t-butoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-cyclohexyloxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-(4-t-butylcyclohexyloxy)carbonylbicyclo[2.2.1]-hept-2-ene,-   5-methyl-5-phenoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-(1-ethoxyethoxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-(1-cyclohexyloxyethoxy)carbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-t-butoxycarbonylmethoxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-tetrahydrofuranyloxycarbonylbicyclo[2.2.1]hept-2-ene,-   5-methyl-5-tetrahydropyranyloxycarbonylbicyclo[2.2.1]hept-2-ene,-   5,6-di(methoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(ethoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(n-propoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(i-propoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(n-butoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(2-methylpropoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(1-methylpropoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(t-butoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(cyclohexyloxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(4-t-butylcyclohexyloxycarbonyl)bicyclo[2.2.1]hept-2-ene,    5,6-di(phenoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(1-ethoxyethoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(1-cyclohexyloxyethoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(t-butoxycarbonylmethoxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(tetrahydrofuranyloxycarbonyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(tetrahydropyranyloxycarbonyl)bicyclo[2.2.1]hept-2-ene and the    like;-   bicyclo[2.2.1]hept-2-ene and bicyclo[2.2.1]hept-2-ene derivatives    such as norbornene (specifically,-   bicyclo[2.2.1]hept-2-ene), 5-methylbicyclo[2.2.1]hept-2-ene,-   5-ethylbicyclo[2.2.1]hept-2-ene,-   5-n-propylbicyclo[2.2.1]hept-2-ene,-   5-n-butylbicyclo[2.2.1]hept-2-ene,-   5-n-pentylbicyclo[2.2.1]hept-2-ene,-   5-n-hexylbicyclo[2.2.1]hept-2-ene,-   5-hydroxybicyclo[2.2.1]hept-2-ene,-   5-carboxybicyclo[2.2.1]hept-2-ene,-   5-hydroxymethylbicyclo[2.2.1]hept-2-ene,-   5-(2-hydroxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-methoxybicyclo[2.2.1]hept-2-ene,-   5-ethoxybicyclo[2.2.1]hept-2-ene,-   5-(1-methoxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5-(1-ethoxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5-(1-n-propoxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5-(1-n-butoxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5-(1-cyclohexyloxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5-methoxycarbonyloxybicyclo[2.2.1]hept-2-ene,-   5-ethoxycarbonyloxybicyclo[2.2.1]hept-2-ene,-   5-n-propoxycarbonyloxybicyclo[2.2.1]hept-2-ene,-   5-n-butoxycarbonyloxybicyclo[2.2.1]hept-2-ene,-   5-(1-methoxyethoxy)methylbicyclo[2.2.1]hept-2-ene,-   5-(1-ethoxyethoxy)methylbicyclo[2.2.1]hept-2-ene,-   5-(1-n-propoxyethoxy)methylbicyclo[2.2.1]hept-2-ene,-   5-(1-n-butoxyethoxy)methylbicyclo[2.2.1]hept-2-ene,-   5-(1-cyclohexyloxyethoxy)methylbicyclo[2.2.1]hept-2-ene,-   5-methoxycarbonyloxymethylbicyclo[2.2.1]hept-2-ene,-   5-ethoxycarbonyloxymethylbicyclo[2.2.1]hept-2-ene,-   5-n-propoxycarbonyloxymethylbicyclo[2.2.1]hept-2-ene,-   5-n-butoxycarbonyloxymethylbicyclo[2.2.1]hept-2-ene,-   5-tetrahydrofuranyloxybicyclo[2.2.1]hept-2-ene,-   5-tetrahydropyranyloxybicyclo[2.2.1]hept-2-ene,-   5-tetrahydrofuranyloxymethylbicyclo[2.2.1]hept-2-ene,-   5-tetrahydropyranyloxymethylbicyclo[2.2.1]hept-2-ene,-   5,6-dihydroxybicyclo[2.2.1]hept-2-ene,-   5,6-dicarboxybicyclo[2.2.1]hept-2-ene,-   5,6-di(hydroxymethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(2-hydroxyethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-dimethoxybicyclo[2.2.1]hept-2-ene,-   5,6-diethoxybicyclo[2.2.1]hept-2-ene,-   5,6-di(1-methoxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5,6-di(1-ethoxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5,6-di(1-n-propoxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5,6-di(1-n-butoxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5,6-di(1-cyclohexyloxyethoxy)bicyclo[2.2.1]hept-2-ene,-   5,6-dimethoxycarbonyloxybicyclo[2.2.1]hept-2-ene,-   5,6-diethoxycarbonyloxybicyclo[2.2.1]hept-2-ene,-   5,6-di-n-propoxycarbonyloxybicyclo[2.2.1]hept-2-ene,-   5,6-di-n-butoxycarbonyloxybicyclo[2.2.1]hept-2-ene,-   5,6-di[(1-methoxyethoxy)methyl]bicyclo[2.2.1]hept-2-ene,-   5,6-di[(1-ethoxyethoxy)methyl]bicyclo[2.2.1]hept-2-ene,-   5,6-di[(1-n-propoxyethoxy)methyl]bicyclo[2.2.1]hept-2-ene,-   5,6-di[(1-n-butoxyethoxy)methyl]bicyclo[2.2.1]hept-2-ene,-   5,6-di[(1-cyclohexyloxyethoxy)methyl]bicyclo[2.2.1]hept-2-ene,-   5,6-di(methoxycarbonyloxymethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(ethoxycarbonyloxymethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(n-propoxycarbonyloxymethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(n-butoxycarbonyloxymethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(tetrahydrofuranyloxy)bicyclo[2.2.1]hept-2-ene,-   5,6-di(tetrahydropyranyloxy)bicyclo[2.2.1]hept-2-ene,-   5,6-di(tetrahydrofuranyloxymethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(tetrahydropyranyloxymethyl)bicyclo[2.2.1]hept-2-ene,-   5-hydroxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-hydroxy-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-carboxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-carboxy-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-Hydroxymethyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-Hydroxymethyl-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-(2-hydroxyethyl)-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(2-hydroxyethyl)-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-methoxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-methoxy-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-ethoxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-ethoxy-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-(1-methoxyethoxy)-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-ethoxyethoxy)-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-n-propoxyethoxy)-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-n-butoxyethoxy)-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-cyclohexyloxyethoxy)-5-methylbicyclo[2.2.1]hept-2-ene,-   5-methoxycarbonyloxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-ethoxycarbonyloxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-n-propoxycarbonyloxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-n-butoxycarbonyloxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-methoxyethoxy)methyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-ethoxyethoxy)methyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-n-propoxyethoxy)methyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-n-butoxyethoxy)methyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(1-cyclohexyloxyethoxy)methyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-methoxycarbonyloxymethyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-ethoxycarbonyloxymethyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-n-propoxycarbonyloxymethyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-n-butoxycarbonyloxymethyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-tetrahydrofuranyloxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-tetrahydropyranyloxy-5-methylbicyclo[2.2.1]hept-2-ene,-   5-tetrahydrofuranyloxymethyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-tetrahydropyranyloxymethyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-hydroxy-6-methylbicyclo[2.2.1]hept-2-ene,-   5-hydroxy-6-ethylbicyclo[2.2.1]hept-2-ene,-   5-carboxy-6-methylbicyclo[2.2.1]hept-2-ene,-   5-carboxy-6-ethylbicyclo[2.2.1]hept-2-ene,-   5-hydroxymethyl-6-methylbicyclo[2.2.1]hept-2-ene,-   5-hydroxymethyl-6-ethylbicyclo[2.2.1]hept-2-ene,-   5-(2-hydroxyethyl)-6-methylbicyclo[2.2.1]hept-2-ene,-   5-(2-hydroxyethyl)-6-ethylbicyclo[2.2.1]hept-2-ene,-   5-methoxy-6-methylbicyclo[2.2.1]hept-2-ene,-   5-methoxy-6-ethylbicyclo[2.2.1]hept-2-ene,-   5-ethoxy-6-methylbicyclo[2.2.1]hept-2-ene,-   5-ethoxy-6-ethylbicyclo[2.2.1]hept-2-ene,-   5-cyanobicyclo[2.2.1]hept-2-ene,-   5-cyanomethylbicyclo[2.2.1]hept-2-ene,-   5-(2-cyanoethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-dicyanobicyclo[2.2.1]hept-2-ene,-   5,6-di(cyanomethyl)bicyclo[2.2.1]hept-2-ene,-   5,6-di(2-cyanoethyl)bicyclo[2.2.1]hept-2-ene,-   5-cyano-5-methylbicyclo[2.2.1]hept-2-ene,-   5-cyano-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-cyanomethyl-5-methylbicyclo[2.2.1]hept-2-ene,-   5-cyanomethyl-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-(2-cyanoethyl)-5-methylbicyclo[2.2.1]hept-2-ene,-   5-(2-cyanoethyl)-5-ethylbicyclo[2.2.1]hept-2-ene,-   5-cyano-6-methylbicyclo[2.2.1]hept-2-ene,-   5-cyano-6-ethylbicyclo[2.2.1]hept-2-ene,-   5-cyanomethyl-6-methylbicyclo[2.2.1]hept-2-ene,-   5-cyanomethyl-6-ethylbicyclo[2.2.1]hept-2-ene,-   5-(2-cyanoethyl)-6-methylbicyclo[2.2.1]hept-2-ene,-   5-(2-cyanoethyl)-6-ethylbicyclo[2.2.1]hept-2-ene,-   5,6-dicarboxybicyclo[2.2.1]hept-2-ene anhydride(hymic acid    anhydride),-   5-(2,2,2-trifluoro-1-hydroxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-methyl-1-hydroxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-trifluoromethyl-1-hydroxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-methoxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-methyl-1-methoxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-trifluoromethyl-1-methoxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-methylcarbonyloxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-methyl-1-methylcarbonyloxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-trifluoromethyl-1-methylcarbonyloxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-t-butoxycarbonyloxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-methyl-1-t-butoxycarbonyloxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2,2,2-trifluoro-1-trifluoromethyl-1-t-butoxycarbonyloxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2-trifluoromethyl-2-hydroxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2-trifluoromethyl-2-methyl-2-hydroxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-[2,2-bis(trifluoromethyl)-2-hydroxyethyl]bicyclo[2.2.1]hept-2-ene,-   5-(2-trifluoromethyl-2-methoxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-(2-trifluoromethyl-2-methyl-2-methoxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-[2,2-bis(trifluoromethyl)-2-methoxyethyl]bicyclo[2.2.1]hept-2-ene,-   5-[2-trifluoromethyl-2-methylcarbonyloxyethyl]bicyclo[2.2.1]hept-2-ene,-   5-(2-trifluoromethyl-2-methyl-2-methylcarbonyloxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-[2,2-bis(trifluoromethyl)-2-methylcarbonyloxyethyl]bicyclo-[2.2.1]hept-2-ene,-   5-[2-trifluoromethyl-2-t-butoxycarbonyloxyethyl]bicyclo-[2.2.1]hept-2-ene,-   5-(2-trifluoromethyl-2-methyl-2-t-butoxycarbonyloxyethyl)bicyclo[2.2.1]hept-2-ene,-   5-[2,2-bis(trifluoromethyl)-2-t-butoxycarbonyloxyethyl]bicyclo[2.2.1]hept-2-ene    and the like;-   tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene derivatives having an    acid-dissociating group which dissociates in the presence of an acid    and forms a carboxyl group in the resin such as-   8-methoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-propoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-i-propoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-butoxycarbonyltetracyclo[4.4.0.1^(2.5).1^(7,10)]dodec-3-ene,-   8-(2-methylpropoxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-methylpropoxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyclohexyloxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,    8-(4-t-butylcyclohexyloxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-phenoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-ethoxyethoxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-cyclohexyloxyethoxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-t-butoxycarbonylmethoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydrofuranyloxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydropyranyloxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-methoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-ethoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-n-propoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-i-propoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-n-butoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-(2-methylpropoxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-(1-methylpropoxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-t-butoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-cyclohexyloxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-(4-t-butylcyclohexyloxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-phenoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-(1-ethoxyethoxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-(1-cyclohexyloxyethoxy)carbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-t-butoxycarbonylmethoxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-tetrahydrofuranyloxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-tetrahydropyranyloxycarbonyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene.-   8,9-di(methoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(ethoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(n-propoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(i-propoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(n-butoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(2-methylpropoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(1-methylpropoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(t-butoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(cyclohexyloxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(4-t-butylcyclohexyloxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(phenoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(1-ethoxyethoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(1-cyclohexyloxyethoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(t-butoxycarbonylmethoxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(tetrahydrofuranyloxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(tetrahydropyranyloxycarbonyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene;-   tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene and other-   tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene derivatives such as:-   tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-propyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-butyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-pentyltetracyclo[4.4.0.1^(2.5).1^(7,10)]dodec-3-ene,-   8-n-hexyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-fluorotetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-fluoromethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-difluoromethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-trifluoromethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-pentafluoroethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,8-difluorotetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-difluorotetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,8-bis(trifluoromethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-bis(trifluoromethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-trifluoromethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,    8,8,9-trifluorotetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,8,9-tris(trifluoromethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,    8,8,9,9-tetrafluorotetracyclo[4.4.0.1^(2.5).1^(7,10)]dodec-3-ene,-   8,8,9,9-tetrakis(trifluoromethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]-dodec-3-ene,-   8,8-difluoro-9,9-bis(trifluoromethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-difluoro-8,9-bis(trifluoromethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,8,9-trifluoro-9-trifluoromethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,8,9-trifluoro-9-trifluoromethoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,8,9-trifluoro-9-pentafluoro-n-propoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-fluoro-8-pentafluoroethyl-9,9-bis(trifluoromethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-difluoro-8-heptafluoro-i-propyl-9-trifluoromethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-chloro-8,9,9-trifluorotetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-dichloro-8,9-bis(trifluoromethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluorocarboethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methyl-8-(2,2,2-Trifluorocarboethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-carboxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-hydroxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-methoxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-ethoxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-n-propoxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-n-butoxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-cyclohexyloxyethoxy)tetracyclo[4.4.0.1^(2.5).1^(7,10)]dodec-3-ene,-   8-methoxycarbonyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxycarbonyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-propoxycarbonyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-butoxycarbonyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-methoxyethoxy)methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-ethoxyethoxy)methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-n-propoxyethoxy)methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-n-butoxyethoxy)methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-cyclohexyloxyethoxy)methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methoxycarbonyloxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxycarbonyloxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-propoxycarbonyloxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-butoxycarbonyloxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydrofuranyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydropyranyloxytetracyclo[4.4.0.1^(2.5).1^(7,10)]dodec-3-ene,-   8-tetrahydrofuranyloxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydropyranyloxymethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene.-   8,9-dihydroxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-dicarboxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(hydroxymethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(2-hydroxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-dimethoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-diethoxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(1-methoxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(1-ethoxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(1-n-propoxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(1-n-butoxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(1-cyclohexyloxyethoxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-dimethoxycarbonyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-diethoxycarbonyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di-n-propoxycarbonyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di-n-butoxycarbonyloxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di[(1-methoxyethoxy)methyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di[(1-ethoxyethoxy)methyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di[(1-n-propoxyethoxy)methyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di[(1-n-butoxyethoxy)methyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di[(1-cyclohexyloxyethoxy)methyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(methoxycarbonyloxymethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(ethoxycarbonyloxymethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,    8,9-di(n-propoxycarbonyloxymethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(n-butoxycarbonyloxymethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(tetrahydrofuranyloxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(tetrahydropyranyloxy)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(tetrahydrofuranyloxymethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(tetrahydropyranyloxymethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene.-   8-hydroxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxy-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-carboxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-carboxy-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxymethyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxymethyl-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-hydroxyethyl)-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-hydroxyethyl)-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methoxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methoxy-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxy-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-methoxyethoxy)-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-ethoxyethoxy)-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-n-propoxyethoxy)-8-methyltetracyclo[4.4.0.1^(2.5).1^(7,10)]dodec-3-ene,-   8-(1-n-butoxyethoxy)-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,    8-(1-cyclohexyloxyethoxy)-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methoxycarbonyloxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxycarbonyloxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-propoxycarbonyloxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-butoxycarbonyloxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene.-   8-(1-methoxyethoxy)methyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-ethoxyethoxy)methyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-n-propoxyethoxy)methyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-n-butoxyethoxy)methyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(1-cyclohexyloxyethoxy)methyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methoxycarbonyloxymethyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxycarbonyloxymethyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-propoxycarbonyloxymethyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-n-butoxycarbonyloxymethyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydrofuranyloxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydropyranyloxy-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydrofuranyloxymethyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-tetrahydropyranyloxymethyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxy-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxy-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-carboxyl-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-carboxyl-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxymethyl-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-hydroxymethyl-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-hydroxyethyl)-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-hydroxyethyl)-9-ethyltetracyclo[4.4.0.1^(2.5).1^(7,10)]dodec-3-ene,-   8-methoxy-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-methoxy-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxy-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-ethoxy-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyanotetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyanomethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-cyanoethyl)tetracyclo[4.4.0.1^(2.5).1^(7,10)]dodec-3-ene,-   8,9-dicyanotetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(cyanomethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-di(2-cyanoethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyano-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyano-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyanomethyl-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyanomethyl-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-cyanoethyl)-8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-cyanoethyl)-8-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyano-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyano-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyanomethyl-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-cyanomethyl-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-cyanoethyl)-9-methyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-cyanoethyl)-9-ethyltetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8,9-dicarboxytetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene    anhydride,-   8-(2,2,2-trifluoro-1-hydroxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-methyl-1-hydroxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-trifluoromethyl-1-hydroxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-methoxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-methyl-1-methoxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-trifluoromethyl-1-methoxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-methylcarbonyloxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-methyl-1-methylcarbonyloxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-trifluoromethyl-1-methylcarbonyloxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-t-butoxycarbonyloxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-methyl-1-t-butoxycarbonyloxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2,2,2-trifluoro-1-trifluoromethyl-1-t-butoxycarbonyloxyethyl)tetracyclo[4.4.0    1^(2,5).1^(7,10)]dodec-3-ene.-   8-(2-trifluoromethyl-2-hydroxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-trifluoromethyl-2-methyl-2-hydroxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-[2,2-bis(trifluoromethyl)-2-hydroxyethyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-trifluoromethyl-2-methoxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-trifluoromethyl-2-methyl-2-methoxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-[2,2-bis(trifluoromethyl)-2-methoxyethyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-[2-trifluoromethyl-2-methylcarbonyloxyethyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-trifluoromethyl-2-methyl-2-methylcarbonyloxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-[2,2-bis(trifluoromethyl)-2-methylcarbonyloxyethyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-[2-trifluoromethyl-2-t-butoxycarbonyloxyethyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-(2-trifluoromethyl-2-methyl-2-t-butoxycarbonyloxyethyl)tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene,-   8-[2,2-bis(trifluoromethyl)-2-t-butoxycarbonyloxyethyl]tetracyclo[4.4.0.1^(2,5).1^(7,10)]dodec-3-ene;-   dicyclopentadiene, tricyclo[5.2.1.0^(2,6)]dec-8-ene,    tricyclo[5.2.1.0^(2,6)]dec-3-ene,-   Tricyclo[4.4.0.1^(2,5)]undec-3-ene,-   tricyclo[6.2.1.0^(1,8)]undec-9-ene,-   Tricyclo[6.2.1.0^(1,8)]undec-4-ene,-   tetracyclo[4.4.0.1^(2,5).1^(7,10).0^(1,6)]dodec-3-ene,-   8-methyltetracyclo[4.4.0.1^(2,5).1^(7,10).0^(1,6)]dodec-3-ene,-   8-ethylidenetetracyclo[4.4.0.1^(2,5).1^(7,12)]dodec-3-ene,-   8-ethylidenetetracyclo[4.4.0.1^(2,5).1^(7,10).0^(1,6)]dodec-3-ene,-   pentacyclo[6.5.1.1^(3,6).0^(2,7).0^(9,13)]pentadec-4-ene,-   pentacyclo[7.4.0.1^(2,5).0^(9,12).0^(8,13)]pentadec-3-ene,

(meth)acrylates such as (meth)acrylic acid esters such as methyl(meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl(meth)acrylate, 2-methylpropyl (meth)acrylate, 2-hydroxyethyl(meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl(meth)acrylate, and compounds shown by the following formula (9),

wherein R represents a hydrogen atom or methyl group;α-hydroxymethylacrylic acid esters such as methyl α-hydroxymethylacrylate, ethyl α-hydroxymethyl acrylate, n-propyl α-hydroxymethylacrylate, and n-butyl α-hydroxymethyl acrylate; vinyl esters such asvinyl acetate, vinyl propionate, and vinyl butyrate; unsaturated nitrilecompounds such as (meth)acrylonitrile, α-chloroacrylonitrile,crotonitrile, maleinitrile, fumaronitrile, mesaconitrile,citraconitrile, and itaconitrile; other unsaturated amide compounds suchas crotonamide, maleinamide, fumaramide, mesaconamide, citraconamide,and itaconamide; other nitrogen-containing vinyl compounds such asN-vinyl-ε-caprolactam, N-vinylpyrrolidone, 2-vinylpyridine,3-vinylpyridine, 4-vinylpyridine, and N-vinylimidazole; unsaturatedcarboxylic acids (anhydrides) such as (meth)acrylic acid, crotonic acid,maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconicanhydride, citraconic acid, citraconic anhydride, and mesaconic acid;carboxyl group-containing esters of unsaturated carboxylic acids such as2-carboxyethyl (meth)acrylate, 2-carboxypropyl (meth)acrylate,3-carboxypropyl (meth)acrylate, 4-carboxybutyl (meth)acrylate;(meth)acryloyloxylactone compounds such as:

-   α-(meth)acryloyloxy-β-methoxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-ethoxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-n-propoxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-i-propoxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-n-butoxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-(2-methylpropoxy)carbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-(1-methylpropoxy)carbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-t-butoxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-cyclohexyloxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-(4-t-butylcyclohexyloxy)carbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-phenoxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-(1-ethoxyethoxy)carbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-(1-cyclohexyloxyethoxy)carbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-t-butoxycarbonylmethoxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-tetrahydrofuranyloxycarbonyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-tetrahydropyranyloxycarbonyl-γ-butyrolactone.-   α-methoxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-ethoxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-n-propoxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-i-propoxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-n-butoxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-(2-methylpropoxy)carbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-(1-methylpropoxy)carbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-t-butoxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-cyclohexyloxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-(4-t-butylcyclohexyloxy)carbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-phenoxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-(1-ethoxyethoxy)carbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-(1-cyclohexyloxyethoxy)carbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-t-butoxycarbonylmethoxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-tetrahydrofuranyloxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-tetrahydropyranyloxycarbonyl-β-(meth)acryloyloxy-γ-butyrolactone.-   α-(meth)acryloyloxy-γ-butyrolactone,-   α-(meth)acryloyloxy-β-fluoro-γ-butyrolactone,-   α-(meth)acryloyloxy-β-hydroxy-γ-butyrolactone,-   α-(meth)acryloyloxy-β-methyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-ethyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β,β-dimethyl-γ-butyrolactone,-   α-(meth)acryloyloxy-β-methoxy-γ-butyrolactone.-   β-(meth)acryloyloxy-γ-butyrolactone,-   α-fluoro-β-(meth)acryloyloxy-γ-butyrolactone,-   α-hydroxy-β-(meth)acryloyloxy-γ-butyrolactone,-   α-methyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-ethyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α,α-dimethyl-β-(meth)acryloyloxy-γ-butyrolactone,-   α-methoxy-β-(meth)acryloyloxy-γ-butyrolactone,-   α-(meth)acryloyloxy-δ-mevalonolactone, compounds in which a carboxyl    group in the above unsaturated carboxylic acids or carboxyl    group-containing esters of unsaturated carboxylic acids is converted    into the following acid-dissociable organic group (ii); and    polyfunctional monomers such as methylene glycol di(meth)acrylate,    ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate,    1,6-hexanediol di(meth)acrylate, 2,5-dimethyl-2,5-hexanediol    di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-nonanediol    di(meth)acrylate, 1,4-bis(2-hydroxypropyl)benzene di(meth)acrylate,    1,3-bis(2-hydroxypropyl)benzene di(meth)acrylate, 1,2-adamantanediol    di(meth)acrylate, 1,3-adamantanediol di(meth)acrylate,    1,4-adamantanediol di(meth)acrylate, tricyclodecanyldimethylol    di(meth)acrylate, and the like.

As examples of the acid-dissociable organic group (ii), groups in whicha hydrogen atom of a carboxyl group is replaced by a substituted methylgroup, 1-substituted ethyl group, 1-branched alkyl group, silyl group,germyl group, alkoxycarbonyl group, acyl group, cyclic organic group(excluding the compounds in which a hydrogen atom in the carboxyl groupin a (meth)acrylic acid is converted to the acid-dissociable group (ii)corresponds to the (meth)acrylic acid derivative (ii)), and the like canbe given.

As examples of a substituted methyl group, a methoxymethyl group,methylthiomethyl group, ethoxymethyl group, ethylthiomethyl group,2-methoxyethoxymethyl group, benzyloxymethyl group, benzylthiomethylgroup, phenacyl group, 4-bromophenacyl group, 4-methoxyphenacyl group,4-methylthiophenacyl group, α-methylphenacyl group, cyclopropylmethylgroup, benzyl group, diphenylmethyl group, triphenylmethyl group,4-bromobenzyl group, 4-nitrobenzyl group, 4-methoxybenzyl group,4-methylthiobenzyl group, 4-ethoxybenzyl group, 4-ethylthiobenzyl group,piperonyl group, methoxycarbonylmethyl group, ethoxycarbonylmethylgroup, n-propoxycarbonylmethyl group, i-propoxycarbonylmethyl group,n-butoxycarbonylmethyl group, t-butoxycarbonylmethyl group, adamantylmethyl group, and the like can be given.

As examples of a 1-substituted ethyl group, a 1-methoxyethyl group,1-methylthioethyl group, 1,1-dimethoxyethyl group, 1-ethoxyethyl group,1-ethylthioethyl group, 1,1-diethoxyethyl group, 1-phenoxyethyl group,1-phenylthioethyl group, 1,1-diphenoxyethyl group, 1-benzyloxyethylgroup, 1-benzylthioethyl group, 1-cyclopropylethyl group, 1-phenylethylgroup, 1,1-diphenylethyl group, 1-methoxycarbonylethyl group,1-ethoxycarbonylethyl group, 1-n-propoxycarbonylethyl group,1-i-propoxycarbonylethyl group, 1-n-butoxycarbonylethyl group,1-t-butoxycarbonylethyl group, and the like can be given.

As examples of a 1-branched alkyl group, an i-propyl group,1-methylpropyl group, t-butyl group, 1,1-dimethylpropyl group,1-methylbutyl group, 1, 1-dimethylbutyl group, and the like can begiven.

As examples of the silyl group, a trimethylsilyl group,ethyldimethylsilyl group, methyldiethylsilyl group, triethylsilyl group,i-propyldimethylsilyl group, methyldi-i-propylsilyl group,tri-i-propylsilyl group, t-butyldimethylsilyl group,methyldi-t-butylsilyl group, tri-t-butylsilyl group, phenyldimethylsilylgroup, methyldiphenylsilyl group, triphenylsilyl group, and the like canbe given.

As examples of the germyl group, a trimethylgermyl group,ethyldimethylgermyl group, methyldiethylgermyl group, triethylgermylgroup, i-propyldimethylgermyl group, methyldi-i-propylgermyl group,tri-i-propylgermyl group, t-butyldimethylgermyl group,methyldi-t-butylgermyl group, tri-t-butylgermyl group,phenyldimethylgermyl group, methyldiphenylgermyl group, triphenylgermylgroup, and the like can be given.

As examples of the alkoxycarbonyl group, a methoxycarbonyl group,ethoxycarbonyl group, i-propoxycarbonyl group, t-butoxycarbonyl group,and the like can be given.

As examples of the acyl group, an acetyl group, propionyl group, butyrylgroup, heptanoyl group, hexanoyl group, valeryl group, pivaloyl group,isovaleryl group, lauryloyl group, myristoyl group, palmitoyl group,stearoyl group, oxalyl group, malonyl group, scucinyl group, glutarylgroup, adipoyl group, piperoyl group, suberoyl group, azelaoyl group,sebacoyl group, acryloyl group, propioloyl group, methacryloyl group,crotonoyl group, oleoyl group, maleoyl group, fumaroyl group, mesaconoylgroup, campholoyl group, benzoyl group, phthaloyl group, isophthaloylgroup, terephthaloyl group, naphthoyl group, toluoyl group,hydroatropoyl group, atropoyl group, cinnamoyl group, furoyl group,thenoyl group, nicotinoyl group, isonicotinoyl group, p-toluenesulfonylgroup, mesyl group, and the like can be given.

As examples of the cyclic organic group, norbornyl group, isobornylgroup, tricyclodecanyl group, carboxytricyclodecanyl group,tetracyclodecanyl group, carboxytetracyclodecanyl group, dicyclopentenylgroup, adamantyl group, cyclopropyl group, cyclopentyl group, cyclohexylgroup, cyclohexenyl group, 4-methoxycyclohexyl group,4-carboxycyclohexyl group, 3-oxocyclohexyl group, tetrahydropyranylgroup, tetrahydrofuranyl group, tetrahydrothiopyranyl group,tetrahydrothiofuranyl group, 3-bromotetrahydropyranyl group,4-methoxytetrahydropyranyl group, 2-oxo-4-methyltetrahydropyranyl group,4-methoxytetrahydrothiopyranyl group, 3-tetrahydrothiophene-1,1-dioxidegroup, and the like can be given.

Of these acid-dissociable organic groups (ii), groups having a formula—COOR′ (wherein R′ represents a (cyclo)alkyl group having 1-19 carbonatoms) or —COOCH₂COOR″ (wherein R″ represents a (cyclo)alkyl grouphaving 1-17 carbon atoms) are preferable, with a 1-methylpropoxycarbonylgroup, t-butoxycarbonyl group, and t-butoxycarbonylmethoxycarbonyl groupbeing particularly preferable.

As a monomer preferably used for providing the other recurring unit{circle over (3)}, 5-n-hexylbicyclo[2.2.1]hept-2-ene, (meth)acrylicacid, maleic anhydride, and a compound having the above formula (9) canbe given. Maleic anhydride exhibits good copolymerizability withnorbornene and its derivatives. Therefore, the molecular weight of theresulting resin can be increased to a desired value by adding maleicanhydride when norbornene derivatives (I) are copolymerized withnorbornene or other norbornene derivatives.

These monomers providing the other recurring unit {circle over (3)} maybe used either individually or in combination of two or more.

In the resin (A3-1), the content of the recurring unit (3-2) is usually0.5-20 mol %, preferably 0.5-15 mol %, and still more preferably 1-10mol %, and the content of the recurring unit having an acid-dissociatinggroup is usually 20-70 mol %, preferably 20-60 mol %, and still morepreferably 30-60 mol %, of the total amount of the recurring units.

In the resin (A3-2), the content of the recurring unit (3-1′) is usually0.5-20mol %, preferably 0.5-15 mol %, and still more preferably 1-10 mol%, and the content of the recurring unit having an acid-dissociatinggroup is usually 20-70 mol %, preferably 20-60 mol %, and still morepreferably 30-60 mol %, of the total amount of the recurring units.

In the resin (α), the content of the recurring unit (3-2) and therecurring unit (3-1′) is usually 1-15 mol %, and preferably 1-10 mol %,the content of the recurring unit (i) and recurring unit (ii) is usually10-90 mol %, preferably 20-90 mol %, and still more preferably 30-70 mol%, and the content of the other recurring units {circle over (3)} isusually 65 mol % or less, and preferably 60 mol % or less, of the totalamount of the recurring units.

In the resin (α1) , the content of the recurring unit (3-2) and therecurring unit (3-1′) is usually 1-15 mol %, and preferably 1-10 mol %,the content of the recurring unit (i) is usually 10-80 mol %, preferably20-80 mol %, and still more preferably 30-60 mol %, and the content ofthe other recurring units {circle over (3)} is usually 65 mol % or less,and preferably 60 mol % or less, of the total amount of the recurringunits.

In the resin (α2), the content of the recurring unit (3-2) and therecurring unit (3-1′) is usually 1-15 mol %, and preferably 1-10 mol %,the content of the recurring unit (ii) is usually 10-80 mol %,preferably 20-70 mol %, and still more preferably 30-60 mol %, and thecontent of the other recurring units {circle over (3)} is usually 50 mol% or less, and preferably 40 mol % or less, of the total amount of therecurring units.

As discussed later, the total content of the recurring unit (3-2) andthe recurring unit (3-1′) in the resins used for the radiation-sensitiveresin composition of the present invention should be sufficiently smalltaking into consideration the action of the resin as a resist. In manycases, industrial manufacture of a resin with such a small content ofthe recurring unit (3-2) and the recurring unit (3-1′) in a stablemanner is difficult. Therefore, the resins (A3-1), (A3-2), (α), (α1),and (α2) are preferably used in combination with other resins which donot contain the recurring units (3-2) and (3-1′), preferably a resincontaining an acid-dissociating group which dissociates in the presenceof an acid and forms a carboxyl group in the resin. The above-describedcontents of the recurring units in the resins used in the presentinvention are thus specified taking stable industrial manufacture ofsuch resins into consideration.

The resins of the present invention can be prepared by copolymerizingthe norbornene derivatives (I) and/or (meth)acrylic acid derivatives(II), preferably together with the norbornene derivatives (i) and/or(meth)acrylic acid derivatives (ii), and optionally monomers providingthe recurring unit {circle over (3)}, in an appropriate solvent using aradical polymerization initiator such as a hydroperoxide, dialkylperoxide, diacyl peroxide, or azo compound and, as required, in thepresence of a chain-transfer agent.

As examples of the solvent used for copolymerization of the components,alkanes such as n-pentane, n-hexane, n-heptane, n-octane, n-nonane, andn-decane; cycloalkanes such as cyclohexane, cycloheptane, cyclooctane,decalin, and norbornane; aromatic hydrocarbons such as benzene, toluene,xylene, ethylbenzene, and cumene; halogenated hydrocarbons such aschlorobutanes, bromohexanes, dichloroethanes, hexamethylene dibromide,and chlorobenzene; saturated carboxylic acid esters such as ethylacetate, n-butyl acetate, i-butyl acetate, and methyl propionate; etherssuch as tetrahydrofuran, dimethoxyethanes, and diethoxyethanes; and thelike can be given.

These solvents may be used either individually or in combination of twoor more.

The copolymerization is carried out at a temerature of usually 40-120°C., and preferably 50-90° C. for usually 1-48 hours, and preferably 1-24hours.

The polystyrene-reduced weight average molecular weight (hereinafterreferred to as “Mn”) of the resins (A3-1), (A3-2), (α), (α1), and (α2)determined by gel permeation chromatography (GPC) is usually3,000-300,000, preferably 4,000-200,000, and still more preferably4,000-100,000. If Mw of these resins is less than 3,000, heat resistanceas a resist tends to decrease; if more than 300,000, developability as aresist tends to decrease.

It is preferable that the above resins contain almost no impurities suchas halogens or metals. The smaller the amount of such impurities, thebetter are the sensitivity, resolution, process stability, patternshape, or the like as a resist. The resin can be purified using, forexample, a chemical purification method such as washing with water orliquid-liquid extraction or a combination of the chemical purificationmethod and a physical purification method such as ultrafiltration orcentrifugation.

In the present invention, the resin (A3-1), (A3-2), (α), (α1), or (α2)may be used either individually or in combination of two or more.

The resin (A3) of the present invention is preferable used together withother resins having a group dissociating in the presence of an acid andforming an acidic functional group, preferably a carboxyl group, in theresin (hereinafter referred to as “other acid-dissociatinggroup-containing resins”).

As examples of such other acid-dissociating group-containing resins,resins containing at least one recurring unit selected from theabove-mentioned recurring unit (i), the recurring unit (ii), and otherrecurring units having an acid-dissociating group, and optionallyfurther containing one or more other recurring units having noacid-dissociating group can be given.

As the other acid-dissociating group-containing resins preferably usedin the present invention, copolymers of at least one compound selectedfrom the group consisting of norbornene derivatives (i) having anacid-dissociating group (i) selected from the group consisting oft-butoxycarbonyl group and the groups shown by the formulas (i-1),(i-2), (i-10), (i-11), (i-13), (i-17), (i-34), (i-35), (i-40), (i-41),(i-46), or (i-47), and having m−0; norbornene derivatives (i) having anacid-dissociating group (i) selected from the group consisting oft-butoxycarbonyl group and the groups shown by the formulas (i-1),(i-2), (i-10), (i-11), (i-13), (i-14), (i-16), (i-17), (i-34), (i-35),(i-40), (i-41), (i-46), or (i-47), and having m−1; norbornenederivatives (IV) having an acid-dissociating group (i) selected from thegroup consisting of t-butoxycarbonyl group and the groups shown by theformulas (i-1), (i-2), (i-10), (i-11), (i-13), (i-14), (i-16), (i-17),(i-34), (i-35), (i-40), (i-41), (i-46), or (i-47); and at least onecompound selected from the group consisting of5-n-hexylbicyclo[2.2.1]hept-2-ene, (meth)acrylic acid, maleic anhydride,and a compound having the above formula (9), can be given.

Maleic anhydride exhibits good copolymerizability with norbornene andits derivatives. Therefore, the molecular weight of the resulting resincan be increased to a desired value by adding maleic anhydride whennorbornene derivatives (i) is copolymerized with norbornene or othernorbornene derivatives.

In the radiation-sensitive resin composition of the present invention,the content of the recurring unit (3-2) and the recurring unit (3-1′) ispreferably 0.01-5 mol %, more preferably 0.1-3 mol %, and particularlypreferably 0.1-1 mol %, the content of the recurring unit having anacid-dissociating group is preferably 10-80 mol %, more preferably 20-60mol %, and still more preferably 30-60 mol %, and the content of theother recurring units is preferably 70 mol % or less, and morepreferably 60 mol % or less, of the total amount of the recurring units.

If the total amount of the recurring units (3-2) and (3-1′) is less than0.01 mol %, it is difficult for the resist to exhibit a sufficienteffect of suppressing line width fluctuations due to an increase ordecrease of space widths. If the amount exceeds 5 mol %, on the otherhand, sensitivity as a resist tends to decrease. If the content of therecurring unit having an acid-dissociating group is less than 10 mol %,resolution as a resist tends to decrease. If the content exceeds 80 mol%, developability tends to decrease and scum tends to be easilyproduced.

The amount of the other acid-dissociating group-containing resins forthe total amount of resin components may be appropriately determined sothat the total content of the recurring units (3-2) and (3-1′) and thecontent of recurring units having an acid-dissociable group may be inthe above range. This amount is usually 70-99.9 wt %, preferably 80-99wt %, and still more preferably 85-95 wt %.

Component (B)

The component (B) of the present invention is a photoacid generatorwhich generates an acid upon exposure (hereinafter referred to as “acidgenerator”).

As examples of the acid generator used in the present invention, (1)onium salt compounds, (2) sulfone compounds, (3) sulfonate compounds,(4) sulfonimide compounds, (5) diazomethane compounds, (6)disulfonylmethane compounds, and (7) halogen-containing compounds can begiven.

Examples of these acid generators will be given below.

(1) Onium Salt Compounds:

As examples of onium salts, iodonium salt, sulfonium salt, phosphoniumsalt, diazonium salt, ammonium salt, pyridinium salt, and the like canbe given.

Specific examples of onium salts include:

-   bis(4-t-butylphenyl)iodonium perfluoro-n-octanesulfonate,-   bis(4-t-butylphenyl)iodonium nonafluoro-n-butanesulfonate,-   bis(4-t-butylphenyl)iodonium trifluoromethanesulfonate,-   bis(4-t-butylphenyl)iodonium pyrenesulfonate,-   bis(4-t-butylphenyl)iodonium n-dodecylbenzenesulfonate,-   bis(4-t-butylphenyl)iodonium hexafluoroantimonate,-   bis(4-t-butylphenyl)iodonium p-toluenesulfonate,-   bis(4-t-butylphenyl)iodonium benzenesulfonate,-   bis(4-t-butylphenyl)iodonium naphthalenesulfonate,-   bis(4-t-butylphenyl)iodonium 10-camphorsulfonate,-   bis(4-t-butylphenyl)iodonium octanesulfonate,-   bis(4-t-butylphenyl)iodonium-   2-trifluoromethylbenzenesulfonate,-   bis(4-t-butylphenyl)iodonium-   4-trifluoromethylbenzenesulfonate,-   bis(4-t-butylphenyl)iodonium 2,4-difluorobenzenesulfonate,-   diphenyliodonium perfluoro-n-octanesulfonate,-   diphenyliodonium nonafluoro-n-butanesulfonate,-   diphenyliodoniumtrifluoromethanesulfonate, diphenyliodonium    pyrenesulfonate, diphenyliodonium n-dodecylbenzenesulfonate,    diphenyliodonium hexafluoroantimonate, diphenyliodonium    p-toluenesulfonate, diphenyliodonium benzenesulfonate,    diphenyliodonium naphthalenesulfonate, diphenyliodonium    10-camphorsulfonate, diphenyliodonium octanesulfonate,-   diphenyliodonium 2-trifluoromethylbenzenesulfonate,-   diphenyliodonium 4-trifluoromethylbenzenesulfonate,-   diphenyliodonium 2,4-difluorobenzenesulfonate,-   triphenylsulfonium perfluoro-n-octanesulfonate,-   triphenylsulfonium nonafluoro-n-butanesulfonate,-   triphenylsulfonium trifluoromethanesulfonate,-   triphenylsulfonium pyrenesulfonate, triphenylsulfonium    n-dodecylbenzenesulfonate, triphenylsulfonium hexafluoroantimonate,    triphenylsulfonium p-toluenesulfonate, triphenylsulfonium    benzenesulfonate, triphenylsulfonium naphthalenesulfonate,    triphenylsulfonium 10-camphorsulfonate, triphenylsulfonium    octanesulfonate, triphenylsulfonium    2-trifluoromethylbenzenesulfonate, triphenylsulfonium    4-trifluoromethylbenzenesulfonate, triphenylsulfonium    2,4-difluorobenzene sulfonate,-   4-t-butylphenyl·diphenylsulfonium nonafluorobutanesulfonate,-   4-t-butylphenyl·diphenylsulfonium trifluoromethanesulfonate.-   4-t-butylphenyl·diphenylsulfonium pyrenesulfonate,-   4-t-butylphenyl·diphenylsulfonium dodecylbenzenesulfonate,-   4-t-butylphenyl·diphenylsulfonium p-toluenesulfonate,-   4-t-butylphenyl·diphenylsulfonium benzenesulfonate,-   4-t-butylphenyl·diphenylsulfonium 10-camphorsulfonate,-   4-t-butylphenyl·diphenylsulfonium octanesulfonate,-   4-t-butylphenyl·diphenylsulfonium-   2-trifluoromethylbenzenesulfonate,-   4-t-butylphenyl·diphenylsulfonium-   4-trifluoromethylbenzenesulfonate,-   4-t-butylphenyl·diphenylsulfonium-   2,4-difluorobenzenesulfonate,-   4-t-butoxyphenyl·diphenylsulfonium nonafluorobutanesulfonate,-   4-hydroxyphenyl·benzyl·methylsulfonium p-toluenesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium    nonafluorobutanesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium    trifluoromethanesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium pyrenesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium dodecylbenzenesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium p-toluenesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium benzenesulfonate.-   2,4,6-tristrimethylphenyl·diphenylsulfonium 10-camphorsulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium octanesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium    2-trifluoromethylbenzenesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium    4-trifluoromethylbenzenesulfonate,-   2,4,6-tristrimethylphenyl·diphenylsulfonium    2,4-difluorobenzenesulfonate,-   cyclohexyl·2-oxocyclohexyl·methylsulfonium    trifluoromethanesulfonate,-   cyclohexyl·2-oxocyclohexyl·methylsulfonium    nonafluoro-n-butanesulfonate,-   cyclohexyl·2-oxocyclohexyl·methylsulfonium    perfluoro-n-octanesulfonate,-   dicyclohexyl·2-oxocyclohexylsulfonium trifluoromethanesulfonate,-   dicyclohexyl·2-oxocyclohexylsulfonium nonafluoro-n-butanesulfonate,-   dicyclohexyl·2-oxocyclohexylsulfonium perfluoro-n-octanesulfonate,-   2-oxocyclohexyldimethylsulfonium trifluoromethanesulfonate,-   2-oxocyclohexyldimethylsulfonium nonafluoro-n-butanesulfonate,-   2-oxocyclohexyldimethylsulfonium perfluoro-n-octanesulfonate,-   4-hydroxyphenyl·phenyl·methylsulfonium p-toluenesulfonate,-   4-hydroxyphenyl·benzyl·methylsulfonium p-toluenesulfonate,-   1-naphthyldimethylsulfonium trifluoromethanesulfonate,-   1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate,-   1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate,-   1-naphthyldiethylsulfonium trifluoromethanesulfonate,-   1-naphthyldiethylsulfonium nonafluoro-n-butanesulfonate,-   1-naphthyldiethylsulfonium perfluoro-n-octanesulfonate,-   4-cyano-1-naphthyldimethylsulfonium trifluoromethanesulfonate,-   4-cyano-1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate,-   4-cyano-1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate,-   4-cyano-1-naphthyldiethylsulfonium trifluoromethanesulfonate,-   4-cyano-1-naphthyldiethylsulfonium nonafluoro-n-butanesulfonate,-   4-cyano-1-naphthyldiethylsulfonium perfluoro-n-octanesulfonate,-   4-nitro-1-naphthyldimethylsulfonium trifluoromethanesulfonate,-   4-nitro-1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate,-   4-nitro-1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate,-   4-nitro-1-naphthyldiethylsulfonium trifluoromethanesulfonate,-   4-nitro-1-naphthyldiethylsulfonium nonafluoro-n-butanesulfonate,-   4-nitro-1-naphthyldiethylsulfonium perfluoro-n-octanesulfonate,-   4-methyl-1-naphthyldimethylsulfonium trifluoromethanesulfonate,-   4-methyl-1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate,-   4-methyl-1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate,-   4-methyl-1-naphthyldiethylsulfonium trifluoromethanesulfonate,-   4-methyl-1-naphthyldiethylsulfonium nonafluoro-n-butanesulfonate,-   4-methyl-1-naphthyldiethylsulfonium perfluoro-n-octanesulfonate,-   4-hydroxy-1-naphthyldimethylsulfonium trifluoromethanesulfonate,-   4-hydroxy-1-naphthyldimethylsulfonium nonafluoro-n-butanesulfonate,-   4-hydroxy-1-naphthyldimethylsulfonium perfluoro-n-octanesulfonate,-   4-hydroxy-1-naphthyldiethylsulfonium trifluoromethanesulfonate,-   4-hydroxy-1-naphthyldiethylsulfonium nonafluoro-n-butanesulfonate,-   4-hydroxy-1-naphthyldiethylsulfonium perfluoro-n-octanesulfonate,-   1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophenium    trifluoromethanesulfonate,-   1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophenium    perfluoro-n-octanesulfonate,-   1-(4-methoxyphenyl)tetrahydrothiophenium trifluoromethanesulfonate,-   1-(4-methoxyphenyl)tetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   1-(4-methoxyphenyl)tetrahydrothiophenium    perfluoro-n-octanesulfonate,-   1-(2,4-dimethoxyphenyl)tetrahydrothiophenium    trifluoromethanesulfonate,-   1-(2,4-dimethoxyphenyl)tetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   1-(2,4-dimethoxyphenyl)tetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-hydroxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate,-   4-methoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate,-   4-ethoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate,-   4-n-propoxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-i-propoxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-n-butoxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-t-butoxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-hydroxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-methoxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-ethoxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-n-propoxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-i-propoxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-n-butoxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-t-butoxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-hydroxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-methoxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-ethoxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-n-propoxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-i-propoxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-n-butoxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-t-butoxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-methoxymethoxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-methoxymethoxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-methoxymethoxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-ethoxymethoxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-ethoxymethoxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-ethoxymethoxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-(1-methoxyethoxy)-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-(1-methoxyethoxy)-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-(1-methoxyethoxy)-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-(2-methoxyethoxy)-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-(2-methoxyethoxy)-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-(2-methoxyethoxy)-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-methoxycarbonyloxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-methoxycarbonyloxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-methoxycarbonyloxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-ethoxycarbonyloxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-ethoxycarbonyloxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-ethoxycarbonyloxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-n-propoxycarbonyloxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-n-propoxycarbonyloxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-n-propoxycarbonyloxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-i-propoxycarbonyloxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-i-propoxycarbonyloxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-i-propoxycarbonyloxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-n-butoxycarbonyloxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-n-butoxycarbonyloxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-n-butoxycarbonyloxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-t-butoxycarbonyloxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-t-butoxycarbonyloxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-t-butoxycarbonyloxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-(2-tetrahydrofuranyloxy)-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-(2-tetrahydrofuranyloxy)-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-(2-tetrahydrofuranyloxy)-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-(2-tetrahydropyranyloxy)-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-(2-tetrahydropyranyloxy)-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-(2-tetrahydropyranyloxy)-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   4-benzyloxy-1-naphthyltetrahydrothiophenium    trifluoromethanesulfonate,-   4-benzyloxy-1-naphthyltetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   4-benzyloxy-1-naphthyltetrahydrothiophenium    perfluoro-n-octanesulfonate,-   1-(1-naphthylacetomethyl)tetrahydrothiophenium    trifluoromethanesulfonate,-   1-(1-naphthylacetomethyl)tetrahydrothiophenium    nonafluoro-n-butanesulfonate,-   1-(1-naphthylacetomethyl)tetrahydrothiophenium    perfluoro-n-octanesulfonate,    (2) Sulfone Compounds:

As examples of sulfone compounds, β-ketosulfone, β-sulfonylsulfone, andα-diazo compounds of these compounds, and the like can be given.

As specific examples of sulfone compounds, phenacylphenylsulfone,mesitylphenacylsulfone, bis(phenylsulfonyl)methane,4-trisphenacylsulfone, and the like can be given.

(3) Sulfonate Compounds:

As examples of sulfonate compounds, alkyl sulfonate, haloalkylsulfonate, aryl sulfonate, imino sulfonate, and the like can be given.

As specific examples of sulfonate compounds, benzointosylate, pyrogalloltristrifluoromethanesulfonate, pyrogallol trisnonafluorobutanesufonate,pyrogallol methanetrisulfonate,nitrobenzyl-9,10-diethoxyanthracene-2-sulfonate,α-methylolbenzointosylate, α-methylolbenzoin octanesulfonate,α-methylolbenzoin trifluoromethanesulfonate, α-methylolbenzoindodecylsulfonate, and the like can be given.

(4) Sulfonimide Compounds:

As examples of sulfonimide compounds, compounds shown by the followingformula (4) can be given:

wherein X represents a divalent group such as an alkylene group, arylenegroup, and alkoxylene group, and R⁷ represents a monovalent group suchas an alkyl group, aryl group, halogenated alkyl group, and halogenatedaryl group.

Specific examples of sulfonimide compounds include:

-   N-(trifluoromethylsulfonyloxy)succinimide,-   N-(trifluoromethylsulfonyloxy)phthalimide,-   N-(trifluoromethylsulfonyloxy)diphenylmaleimide,-   N-(trifluoromethylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(trifluoromethylsulfonyloxy)-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(trifluoromethylsulfonyloxy)bicyclo[2.2.1]heptan-5,6-oxy-2,3-dicarboxyimide,-   N-(trifluoromethylsulfonyloxy)naphthylimide,-   N-(nonafluorobutylsulfonyloxy)succinimide,-   N-(nonafluorobutylsulfonyloxy)phthalimide,-   N-(nonafluorobutylsulfonyloxy)diphenylmaleimide,-   N-(nonafluorobutylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(nonafluorobutylsulfonyloxy)-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(nonafluorobutylsulfonyloxy)bicyclo[2.2.1]heptan-5,6-oxy-2,3-dicarboxyimide,-   N-(nonafluorobutylsulfonyloxy)naphthylimide,-   N-(2-trifluoromethylbenzenesulfonyloxy)succinimide,-   N-(2-trifluoromethylbenzenesulfonyloxy)phthalimide,-   N-(2-trifluoromethylbenzenesulfonyloxy)diphenylmaleimide,-   N-(2-trifluoromethylbenzenesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(2-trifluoromethylbenzenesulfonyloxy)-7-oxabicyclo-[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(2-trifluoromethylbenzenesulfonyloxy)bicyclo[2.2.1]-heptan-5,6-oxy-2,3-dicarboxyimide,-   N-(2-trifluoromethylbenzenesulfonyloxy)naphthylimide,-   N-(10-camphorsulfonyloxy)succinimide,-   N-(10-camphorsulfonyloxy)phthalimide,-   N-(10-camphorsulfonyloxy)diphenylmaleimide,-   N-(10-camphorsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(10-camphorsulfonyloxy)-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(10-camphorsulfonyloxy)bicyclo[2.2.1]heptan-5,6-oxy-2,3-dicarboxyimide,    N-(10-camphorsulfonyloxy)naphthylimide,-   N-(p-toluenesulfonyloxy)succinimide,-   N-(p-toluenesulfonyloxy)phthalimide,-   N-(p-toluenesulfonyloxy)diphenylmaleimide,-   N-(p-toluenesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(p-toluenesulfonyloxy)-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(p-toluenesulfonyloxy)bicyclo[2.2.1]heptane-5,6-oxy-2,3-dicarboxyimide,    N-(p-toluenesulfonyloxy)naphthylimide,    and compounds shown by the following formulas (4-1) to (4-6),    wherein A individually indicates an organic group having 2-10 carbon    atoms and an ester bond, B individually represents an alkyl group    having 1-10 carbon atoms or an alkoxyl group having 1-10 carbon    atoms, m is an integer of 1-11, and n is an integer of 0-10,    provided that m+n≦11.    (5) Diazomethane Compounds:

As examples of diazomethane compounds, compounds shown by the followingformula (5) can be given:

wherein R⁸ and R⁹ individually represent a monovalent group such as analkyl group, aryl group, halogenated alkyl group, and halogenated allylgroup.

As specific examples of diazomethane compound,

-   bis(trifluoromethylsulfonyl)diazomethane,-   bis(t-butylsulfonyl)diazomethane,-   bis(cyclohexylsulfonyl)diazomethane,-   bis(phenylsulfonyl)diazomethane,-   bis(p-toluenesulfonyl)diazomethane,-   methylsulfonyl-p-toluenesulfonyldiazomethane,-   1-cyclohexylsulfonyl-1-(1,1-dimethylethylsulfonyl)diazomethane,-   bis(1,1-dimethylethylsulfonyl)diazomethane,    and a compound shown by the following formulas (5-1) can be given.    (6) Disulfonylmethane Compounds

As examples of disulfonylmethane compounds, a compound shown by thefollowing formula (6) can be given:

wherein R¹⁰ and R¹¹ individually represent a linear or branched alkylgroup, cycloalkyl group, aryl group, aralkyl group, or a monovalentorganic group having a hetero atom, Y and Z individually represent anaryl group, a hydrogen atom, a linear or branched alkyl group, amonovalent organic group having a hetero atom, provided that at leastone of Y and Z represents an aryl group, or Y and Z bond to form amonocyclic or polycyclic ring having at least one unsaturated bond, or Yand Z bond to form a group shown by the following formula:

wherein Y′ and Z′ individually represent a hydrogen atom, halogen atom,alkyl group, cycloalkyl group, aryl group, or aralkyl group, or Y′ andZ′ bond to form a monocyclic carbon structure, and n is an integer of2-10.

As preferable examples of disulfonylmethane compounds, compounds shownby the following formulas (7) to (14) can be given.

(7) Halogen-Containing Compounds:

As examples of halogen-containing compounds, haloalkyl group-containinghydrocarbon compounds, haloalkyl group-containing heterocycliccompounds, and the like can be given.

As specific examples of preferable halogen-containing compounds,(trichloromethyl)-s-triazine derivatives such asphenylbis(trichloromethyl)-s-triazine,4-methoxyphenylbis(trichloromethyl)-s-triazine, and1-naphthylbis(trichloromethyl)-s-triazine,1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane, and the like can begiven.

Of these acid generators, compounds having a boiling point higher than165° C. at normal pressure are preferable.

Particularly preferable compounds are: bis(4-t-butylphenyl)iodoniumnonafluorobutanesulfonate, bis(4-t-butylphenyl)iodoniumdodecylbenzenesulfonate, bis(4-t-butylphenyl)iodoniump-toluenesulfonate, bis(4-t-butylphenyl)iodonium 10-camphorsulfonate,bis(4-t-butylphenyl)iodonium octanesulfonate, diphenyliodoniump-toluenesulfonate, diphenyliodonium benzenesulfonate, diphenyliodonium10-camphorsulfonate, diphenyliodonium octanesulfonate, diphenyliodoniumnonafluorobutanesulfonate, diphenyliodonium dodecylbenzenesulfonate,triphenylsulfonium nonafluorobutanesulfonate, triphenylsulfonium10-camphorsulfonate, triphenylsulfonium naphthalenesulfonate,

-   4-t-butoxyphenyldiphenylsulfonium nonafluorobutanesulfonate,-   4-hydroxyphenylbenzylmethylsulfonium p-toluenesulfonate,-   N-(nonafluorobutylsulfonyloxy)succinimide,-   N-(nonafluorobutylsulfonyloxy)phthalimide,-   N-(nonafluorobutylsulfonyloxy)diphenylmaleimide,-   N-(nonafluorobutylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide,-   N-(nonafluorobutylsulfonyloxy)-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(nonafluorobutylsulfonyloxy)bicyclo[2.2.1]heptan-5,6-oxy-2,3-dicarboxyimide,-   N-(nonafluorobutylsulfonyloxy)naphthylimide,-   N-(10-camphorsulfonyloxy)succinimide,-   N-(10-camphorsulfonyloxy)phthalimide,-   N-(10-camphorsulfonyloxy)diphenylmaleimide,-   N-(10-camphorsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(10-camphorsulfonyloxy)-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide,-   N-(10-camphorsulfonyloxy)bicyclo[2.2.1]heptan-5,6-oxy-2,3-dicarboxyimide,    and-   N-(10-camphorsulfonyloxy)naphthylimide.

In the present invention, the acid generators can be used eitherindividually or in combination of two or more. The amount of the acidgenerators to be added is 0.5-20 parts by weight, and preferably 1-10parts by weight for 100 parts by weight of the copolymer components whenthe copolymer (A1) or copolymer (A2) is used. When the copolymer (A3) isused, the amount of the acid generators is 0.1-10 parts by weight, andpreferably 0.5-7 parts by weight for 100 parts by weight of thecopolymer components.

Component (C)

The component (C) of the negative tone radiation sensitive compositionof the present invention is a compound crosslinkable with the copolymer(A2) in the presence of an acid (an acid generated by exposure, forexample), for example, a compound having one or more functional groupsexhibiting crosslinking reactivity with the copolymer (A2) (such acompound and functional group are hereinafter referred to respectivelyas “a crosslinking agent” and “a crosslinkable functional group”).

The groups shown by the following formulas (15) to (19) can be given asexamples of the crosslinkable functional group,

wherein k is an integer of 1 or 2, Q¹ indicates a single bond, —O—, —S—,—COO—, or —NH— when k=1 and a trivalent nitrogen atom when k=2, Q² is—O— or —S—, i is an integer of 0-3, and j is an integer of 1-3, providedthat i+j is 1 to 4,

wherein Q³ is —O—, —CO—, or —COO—, R¹² and R¹³ individually represent ahydrogen atom or alkyl group having 1-4 carbon atoms, R¹⁴ represents analkyl group having 1-5 carbon atoms, aryl group having 6-12 carbonatoms, or aralkyl group having 7-14 carbon atoms, and y is an integer of1 or more,

wherein R¹⁵, R¹⁶, and R¹⁷ individually represent a hydrogen atom or analkyl group having 1-4 carbon atoms,

wherein R¹², R¹³, and y are the same as defined in the formula (16) andR¹⁸ and R¹⁹ individually represent an alkyl group having 1-5 carbonatoms or an alkylol group having 1-5 carbon atoms, and

wherein R¹², R¹³, and y are the same as defined in the formula (16), andR²⁰ represents a divalent organic group having a 3-8 member cyclicstructure containing a hetero atom selected from an oxygen atom, sulfuratom, and nitrogen atom.

As specific examples of such a crosslinkable functional group, aglycidyl ether group, glycidyl ester group, glycidyl amino group,methoxymethyl group, ethoxymethyl group, benzyloxymethyl group,acetoxymethyl group, benzoiloxy methyl group, formyl group, acetylgroup, vinyl group, iso-propenyl group, dimethylaminomethyl group,diethylolaminomethyl group, morpholinomethyl group, and the like can begiven.

As examples of the compound having such a crosslinkable functionalgroup, a bisphenol A epoxy compound, bisphenol F epoxy compound,bisphenol S epoxy compound, novolac resin epoxy compound, resol resinepoxy compound, poly(hydroxystyrene) epoxy compound, methylolgroup-containing melamine compound, methylol group-containingbenzoquanamine compound, methylol group-containing urea compound,methylol group-containing phenol compound, alkoxyalkyl group-containingmelamine compound, alkoxyalkyl group-containing benzoquanamine compound,alkoxyalkyl group-containing urea compound, alkoxyalkyl group-containingphenol compound, carboxymethyl group-containing melamine resin,carboxymethyl group-containing benzoquanamine resin, carboxymethylgroup-containing urea resin, carboxymethyl group-containing phenolresin, carboxymethyl group-containing melamine compound, carboxymethylgroup-containing benzoquanamine compound, carboxymethyl group-containingurea compound, carboxymethyl group-containing phenol compound, and thelike can be given.

Of these compounds having crosslinkable functional groups, a methylolgroup-containing phenol compound, methoxymethyl group-containingmelamine compound, methoxymethyl group-containing phenol compound,methoxymethyl group-containing glycoluril compound, methoxymethylgroup-containing urea compound, and acetoxymethyl group-containingphenol compound are preferable, with particularly preferable compoundsbeing a methoxymethyl group-containing melamine compound (for example,hexamethoxymethylmelamine), methoxymethyl group-containing glycolurilcompound, methoxymethyl group-containing urea compound, and the like.Methoxymethyl group-containing melamine compounds are commerciallyavailable under the trademarks CYMEL300, CYMEL301, CYMEL303, andCYMEL305 (manufactured by Mitsui Cyanamid Co., Ltd.), methoxymethylgroup-containing glycoluril compounds are commercially available underthe trademark CYMEL 1174 (manufactured by Mitsui Cyanamid Co., Ltd.) andthe like; and methoxymethyl group-containing urea compounds arecommercially available under the trademark MX290 (manufactured by SanwaChemical Co., Ltd.) and the like.

A compound exhibiting a crosslinking function obtained by replacing ahydrogen atom of an acid functional group in the copolymer (A2) with theabove-mentioned crosslinkable functional group can also be suitably usedas a crosslinking agent. The amount of the crosslinkable functionalgroup introduced is usually 5-60 mol %, preferably 10-50 mol %, andstill more preferably 15-40 mol % of the total acid functional groups inthe copolymer (A2), although the specific percentage varies depending ontypes of crosslinkable functional group and the alkali-soluble resininto which the crosslinkable functional group is introduced. The amountof crosslinkable functional group less than 5 mol % may decrease therate of residual coatings and tends to induce meandering and swelling ofthe patterns. If the amount exceeds 60 mol %, developability of exposedareas tends to decrease.

Methoxymethyl group-containing compounds such as dimethoxymethyl ureaand tetramethoxymethyl glycoluril are particularly preferable as thecrosslinking agent. These crosslinking agents may be used eitherindividually or in combination of two or more.

Other Additives

It is preferable to add an acid diffusion controller to the positivetone radiation-sensitive resin composition of the present invention. Theacid diffusion controller controls diffusion of an acid generated fromthe acid generator upon exposure in the resist film to hinder undesiredchemical reactions in the unexposed area.

Use of such an acid diffusion controller improves the storage stabilityof the composition and resolution as a resist. Moreover, line widthchange of the resist pattern due to fluctuation of PED can becontrolled, whereby remarkably superior process stability can beachieved.

As the acid diffusion controller, organic compounds containing nitrogenof which the basicity does not change during exposure or heating forforming a resist pattern are preferable.

As examples of such nitrogen-containing organic compounds, a compoundshown by the following formula (20) (hereinafter called“nitrogen-containing compound (I)”),

wherein R²¹, R²², and R²³ individually represent a hydrogen atom, alkylgroup having 1-15 carbon atoms, aryl group having 6-15 carbon atoms, oraralkyl group having 7-15 carbon atoms, a diamino compound having twonitrogen atoms in the molecule (hereinafter referred to as“nitrogen-containing compound (II)”), a diamino polymer having three ormore nitrogen atoms in the molecule (hereinafter referred to as“nitrogen-containing compound (III)”), an amide group-containingcompound, urea compound, nitrogen-containing heterocyclic compound, andthe like can be given.

Examples of the nitrogen-containing compound (I) include monoalkylaminessuch as n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, andn-decylamine; dialkylamines such as di-n-butylamine, di-n-pentylamine,di-n-hexylamine, di-n-heptylamine, di-n-octylamine, di-n-nonylamine, anddi-n-decylamine; trialkylamines such as triethylamine,tri-n-propylamine, tri-n-butylamine, tri-n-pentylamine,tri-n-hexylamine, tri-n-heptylamine, tri-n-octylamine, tri-n-nonylamine,tri-n-decylamine, and tri-n-dodecylamine; aromatic amines such asaniline, N-methylaniline, N,N-dimethylaniline, 2-methylaniline,3-methylaniline, 4-methylaniline, 4-nitroaniline, diphenylamine,triphenylamine, and 1-naphthylamine; and trialcoholamines such astriethanolamine.

Examples of the nitrogen-containing compounds (II) includeethylenediamine, N,N,N′,N′-tetramethylethylenediamine,tetramethylenediamine, hexamethylenediamine,4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether,4,4′-diaminobenzophenone, 4,4′-diaminodiphenylamine,2,2′-bis(4-aminophenyl)propane,2-(3-aminophenyl)-2-(4-aminophenyl)propane,2-(4-aminophenyl)-2-(3-hydroxyphenyl)propane,2-(4-aminophenyl)-2-(4-hydroxyphenyl)propane,1,4-bis[1-(4-aminophenyl)-1-methylethyl]benzene,1,3-bis[1-(4-aminophenyl)-1-methylethyl]benzene, and the like.

As examples of the nitrogen-containing compound (III),polyethyleneimine, polyallylamine, and the like can be given.

Examples of compounds containing an amide group include formamide,N-methylformamide, N,N-dimethylformamide, acetamide, N-methylacetamide,N,N-dimethylacetamide, propionamide, benzamide, pyrrolidone,N-methylpyrrolidone, and the like.

Examples of urea compounds include urea, methylurea, 1,1-dimethylurea,1,3-dimethylurea, 1,1,3,3-tetramethylurea, 1,3-diphenylurea,tributylthiourea, and the like.

Examples of the nitrogen-containing heterocyclic compounds includeimidazoles such as imidazole, benzimidazole, 4-methylimidazole,4-methyl-2-phenylimidazole, 2-phenylbenzimidazole,1-t-butoxycarbonyloxy-2-phenylbenzimidazole; pyridines such as pyridine,2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine,2-phenylpyridine, 4-phenylpyridine, N-methyl-4-phenylpyridine, nicotine,nicotinic acid, nicotinamide, nicotinbenzyl, quinoline, 8-oxyquinoline,and acridine; pyrazine, pyrazole, pyridazine, quinoxaline, purine,pyrrolidine, piperidine, piperidine ethanol, morpholine,4-methylmorpholine, piperazine, 1,4-dimethylpiperazine,1,4-diazabicyclo[2.2.2]octane; and the like.

Of these nitrogen-containing organic compounds, the nitrogen-containingcompound (I) and the nitrogen-containing heterocyclic compound arepreferable. Trialkylamines are particularly preferable among thenitrogen-containing compound (I), and pyridines are particularlypreferable among the nitrogen-containing heterocyclic compounds.

In the present invention, the acid diffusion controllers can be usedeither individually or in combination of two or more.

The amount of the acid diffusion controller to be used is usually0.001-15 parts by weight, preferably 0.001-10 parts by weight, and stillmore preferably 0.005-5 parts by weight for 100 parts by weight of thecopolymer components. If the amount of the acid diffusion controller isto small, resolution as a resist and PED stability tends to be impaired;if too large, sensitivity as a resist and developability of exposedareas tend to decrease.

If necessary, a surfactant may be added to the positive toneradiation-sensitive resin composition of the present invention toimprove coatability of the composition, striation, developability as aresist, and the like.

Examples of such a surfactant include polyoxyethylene lauryl ether,polyoxyethylene stearyl ether, polyoxyethylene oleyl ether,polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether,polyethylene glycol dilaurate, polyethylene glycol distearate; andcommercially available products such as FTOP EF301, EF303, EF352(manufactured by TOHKEM PRODUCTS CORPORATION), MEGAFAC F171, F173(manufactured by Dainippon Ink and Chemicals, Inc.), Fluorad FC430,FC431 (manufactured by Sumitomo 3M Ltd.), Asahi Guard AG710, SurflonS-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-106 (manufactured byAsahi Glass Co., Ltd.), KP341 (manufactured by Shin-Etsu Chemical Co.,Ltd.), and Polyflow No. 75, No. 95 (manufactured by Kyoeisha ChemicalCo., Ltd.).

The amount of the surfactants to be added is usually 2 parts by weightor less for 100 parts by weight of the copolymer components.

In addition, a sensitizer may be added to the positive tone or negativetone radiation sensitive composition of the present invention. Thesensitizer absorbs energy of radiation and transmits the energy to theacid generator, thereby increasing the amount of an acid to be generatedupon exposure. The sensitizer also improves apparent sensitivity of aresist.

As preferable examples of the sensitizers, benzophenones, rose bengals,anthracenes, carbazoles, and the like can be given.

The amount of sensitizers to be added is usually 50 parts by weight orless for 100 parts by weight of the component (A).

In addition, a dye and/or a pigment may be added to visualize latentimages of exposed areas and to reduce the effect of halation duringexposure. An adhesion adjuvant may be added to improve adhesiveness tothe substrate.

As other additives, halation inhibitors such as4-hydroxy-4′-methylchalcone, form improvers, preservation stabilizers,antifoaming agents, and the like can also be added.

Preparation and Use of Composition

The radiation-sensitive resin composition of the present invention isprepared into a composition solution when used by homogeneouslydissolving the composition in a solvent so that the total solidconcentration is 5-50 wt %, and preferably 10-40 wt %, and filtering thesolution using a filter with a pore diameter of about 0.2 μm.

Examples of solvents used for the preparation of the compositionsolution include: ethylene glycol monoalkyl ether acetates such asethylene glycol monomethyl ether acetate, ethylene glycol monoethylether acetate, ethylene glycol mono-n-propyl ether acetate, and ethyleneglycol mono-n-butyl ether acetate; propylene glycol monoalkyl etherssuch as propylene glycol monomethyl ether, propylene glycol monoethylether, propylene glycol mono-n-propyl ether, and propylene glycolmono-n-butyl ether; propylene glycol dialkyl ethers such as propyleneglycol dimethyl ether, propylene glycol diethyl ether, propylene glycoldi-n-propyl ether, and propylene glycol di-n-butyl ether; propyleneglycol monoalkyl ether acetates such as propylene glycol monomethylether acetate, propylene glycol monoethyl ether acetate, propyleneglycol mono-n-propyl ether acetate, and propylene glycol mono-n-butylether acetate; lactic acid esters such as methyl lactate, ethyl lactate,n-propyl lactate, and i-propyl lactate; aliphatic carboxylic acid esterssuch as n-amyl formate, i-amyl formate, ethyl acetate, n-propyl acetate,i-propyl acetate, n-butyl acetate, i-butyl acetate, n-amyl acetate,i-amyl acetate, i-propyl propionate, n-butyl propionate, and i-butylpropionate; other esters such as ethyl hydroxyacetate, ethyl.2-hydroxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutyrate, ethylmethoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate, ethyl3-methoxypropionate, methyl 3-ethoxypropionate, ethyl3-ethoxypropionate, butyl 3-methoxyacetate, butyl3-methyl-3-methoxyacetate, butyl 3-methyl-3-methoxypropionate, butyl3-methyl-3-methoxybutyrate, methyl acetoacetate, ethyl acetoacetate,methyl pyruvate, and ethyl pyruvate; aromatic hydrocarbons such astoluene and xylene; ketones such as methyl ethyl ketone, methyl propylketone, methyl butyl ketone, 2-heptanone, 3-heptanone, 4-heptanone, andcyclohexanone; amides such as N-methylformamide, N,N-dimethylformamide,N-methylacetamide, N,N-dimethyl acetamide, and N-methylpyrrolidone; andlactones such as γ-butyrolactone.

These solvents may be used either individually or in combinations of twoor more.

Formation of Resist Patterns

A resist pattern is formed from the radiation-sensitive resincomposition of the present invention by applying the compositionsolution prepared as mentioned above to substrates such as a siliconwafer or a wafer covered with aluminum using an appropriate applicationmethod such as rotational coating, cast coating, and roll coating toform a resist film. The resist film is then optionally heated at atemperature of about 70-160° C. (hereinafter referred to as “pre-bake”)and exposed to light through a predetermined mask pattern. Radiationused here can be appropriately selected according to the types of acidgenerator from among ultraviolet rays such as i-line (wavelength: 365mm), ultraviolet rays such as ArF excimer laser (wavelength: 193 nm) orKrF excimer laser (wavelength: 248 nm), X-rays such as synchrotronradiation, and charged particle rays such as electron beams. Theexposure conditions such as the amount of exposure are appropriatelydetermined depending on the composition of the radiation-sensitive resincomposition, types of additives, and the like.

In the present invention, it is preferable to heat the resist at 90-160°C. for 30 second or more after exposure (hereinafter referred to as“post-exposure bake”) in order to stably form high precision resistpatterns exhibiting excellent resolution, developability, and patternform, free from a pattern skirting problem, and exhibiting superior PED.If the temperature for post-exposure bake is less than 90° C., not onlythe effect of PED stability tends to be impaired, but also resistpatterns tend to produce a skirt according to the resist pattern formingconditions such as a resist thickness when the patterns are formed on anSiN substrate or a BPSG substrate having an SiO₂ film in which ions suchas boron ions phosphorous ions are injected. Such a resin compositionmay not be used in actual devices.

The exposed resist film is then developed using an alkaline developer at10-50° C. for 30-200 seconds to form a predetermined resist pattern.

As the alkaline developer, an alkaline aqueous solution prepared bydissolving an alkali such as an alkali metal hydroxide, aqueous ammonia,mono-, di-, or tri-alkylamine, mono-, di-, or tri-alkanolamine,heterocyclic amine, tetraalkylammonium hydroxide, choline,1,8-diazabicyclo[5.4.0]-7-undecene, or 1,5-diazabicyclo[4.3.0]-5-noneneto a concentration of 1-10 wt %, and preferably 1-5 wt % can be used.

Moreover, an appropriate amount of a water-soluble organic solvent suchas methanol and ethanol or a surfactant can be added to the developercomprising the above alkaline aqueous solution.

When using the developer comprising the alkaline aqueous solution, theresist film is washed with water after development.

When forming a resist pattern, a protective film may be provided on theresist film in order to prevent an adverse effect of basic impuritiesand the like which are present in the environmental atmosphere.

EXAMPLES

The embodiments of the present invention will be described in moredetail by examples. However, these examples should not be construed aslimiting the present invention.

Synthesis Examples of Component (A1)

Synthesis Example 1

86 g of p-acetoxystyrene, 5 g of styrene, 40 g of p-t-butoxystyrene, 11g of N,N-dimethylacrylamide, 6 g of azobisisobutyronitrile (hereinafterreferred to as “AIBN”), and 1 g of t-dodecylmercaptan were dissolved in160 g of propylene glycol monomethyl ether. The mixture was polymerizedfor 16 hours at 70° C. in a nitrogen atmosphere. After polymerization,the reaction solution was added dropwise to a large quantity of hexaneto coagulate and purify the resulting resin. After the addition of 150 gof propylene glycol monomethyl ether to the resin, 300 g of methanol, 80g of triethylamine, and 15 g of water were added. The mixture washydrolyzed for 8 hours while refluxing at the boiling point. After thereaction, the solvent and triethylamine were evaporated under reducedpressure. The resulting resin was dissolved in acetone and was addeddropwise to a large quantity of water to coagulate the resin. Theresulting white powder was filtered and dried overnight at 50° C. underreduced pressure.

The resin was found to have Mw and Mw/Mn of 16,000 and 1.7 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization molarratio of p-hydroxystyrene, styrene, p-t-butoxystyrene, andN,N-dimethylacrylamide of the copolymer was 62:5:23:10. This resin isreferred to as a “resin (A-1)”.

Synthesis Example 2

80 g of p-acetoxystyrene, 19 g of t-butylacrylate, 35 g ofp-t-butoxystyrene, 11 g of N,N-dimethylacrylamide, 6 g of AIBN, and 1 gof t-dodecylmercaptan were dissolved in 230 g of propylene glycolmonomethyl ether. The mixture was polymerized for 16 hours at 70° C. ina nitrogen atmosphere. After polymerization, the reaction solution wasadded dropwise to a large quantity of hexane to coagulate and purify theresulting resin. After the addition of 150 g of propylene glycolmonomethyl ether to the purified resin, 300 g of methanol, 80 g oftriethylamine, and 15 g of water were added. The mixture was hydrolyzedfor eight hours while refluxing at a boiling point. After the reaction,the solvent and triethylamine were evaporated under reduced pressure.The resulting resin was dissolved in acetone and added dropwise to alarge quantity of water to coagulate the resin. The resulting whitepowder was filtered and dried overnight at 50° C. under reducedpressure.

The resin was found to have Mw and Mw/Mn of 11,500 and 1.6 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization molarratio of p-hydroxystyrene, t-butyl acrylate, p-t-butoxystyrene, andN,N-dimethylacrylamide of the copolymer was 55:15:20:10. This resin isreferred to as a “resin (A-2)”.

Synthesis Example 3

91 g of p-acetoxystyrene, 50 g of p-t-butoxystyrene, 11 g ofN,N-dimethylacrylamide, 6 g of AIBN, and 1 g of t-dodecylmercaptan weredissolved in 160 g of propylene glycol monomethyl ether. The mixture waspolymerized for 16 hours at 70° C. in a nitrogen atmosphere. Afterpolymerization, the reaction solution was added dropwise to a largequantity of hexane to coagulate and purify the resulting resin. Afterthe addition of 150 g of propylene glycol monomethyl ether to the resin,300 g of methanol, 80 g of triethylamine, and 15 g of water were added.The mixture was hydrolyzed for 8 hours while refluxing at the boilingpoint. After the reaction, the solvent and triethylamine were evaporatedunder reduced pressure. The resulting resin was dissolved in acetone andadded dropwise to a large quantity of water to coagulate the resin. Theresulting white powder was filtered and dried overnight at 50° C. underreduced pressure.

The resin was found to have-Mw and Mw/Mn of 16,000 and 1.7 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization ratioof p-hydroxystyrene, p-t-butoxystyrene, and N,N-dimethylacrylamide ofthe copolymer was 62:28:10. This resin is referred to as a “resin(A-3)”.

Synthesis Example 4

146 g of p-acetoxystyrene, 11 g of N,N-dimethylacrylamide, 6 g of AIBN,and 1 g of t-dodecylmercaptan were dissolved in 160 g of propyleneglycol monomethyl ether. The mixture was polymerized for 16 hours at 70°C. in a nitrogen atmosphere. After polymerization, the reaction solutionwas added dropwise to a large quantity of hexane to coagulate and purifythe resulting resin. After the addition of 150 g of propylene glycolmonomethyl ether to the resin, 300 g of methanol, 80 g of triethylamine,and 15 g of water were added. The mixture was hydrolyzed for 8 hourswhile refluxing at the boiling point. After the reaction, the solventand triethylamine were evaporated under reduced pressure. The resultingresin was dissolved in acetone and added dropwise to a large quantity ofwater to coagulate the resin. The resulting white powder was filteredand dried overnight at 50° C. under reduced pressure.

The resin was found to have Mw and Mw/Mn of 16,000 and 1.7 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization ratioof p-hydroxystyrene and N,N-dimethylacrylamide was 90:10. This resin isreferred to as a “resin (A-4)”.

Synthesis Example 5

86 g of p-acetoxystyrene, 5 g of styrene, 40 g of p-t-butoxystyrene, 28g of 1-acryloyl-2-phenylbenzimidazole, 6 g of AIBN, and 1 g oft-dodecylmercaptan were dissolved in 160 g of propylene glycolmonomethyl ether. The mixture was polymerized for 16 hours at 70° C. ina nitrogen atmosphere. After polymerization, the reaction solution wasadded dropwise to a large quantity of hexane to coagulate and purify theresulting resin. After the addition of 150 g of propylene glycolmonomethyl ether to the resin, 300 g of methanol, 80 g of triethylamine,and 15 g of water were added. The mixture was hydrolyzed for 8 hourswhile refluxing at the boiling point. After the reaction, the solventand triethylamine were evaporated under reduced pressure. The resultingresin was dissolved in acetone and added dropwise to a large quantity ofwater to coagulate the resin. The resulting white powder was filteredand dried overnight at 50° C. under reduced pressure.

The resin was found to have Mw and Mw/Mn of 16,000 and 1.7 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization molarratio of p-hydroxystyrene, styrene, p-t-butoxystyrene, and1-acryloyl-2-phenylbenzimidazole of the copolymer was 62:5:23:10. Thisresin is referred to as a “resin (A-5)”.

Synthesis Example 6

80 g of p-acetoxystyrene, 19 g of t-butylacrylate, 35 g ofp-t-butoxystyrene, 28 g of 1-acryloyl-2-phenylbenzimidazole, 6 g ofAIBN, and 1 g of t-dodecylmercaptan were dissolved in 230 g of propyleneglycol monomethyl ether. The mixture was polymerized for 16 hours at 70°C. in a nitrogen atmosphere. After polymerization, the reaction solutionwas added dropwise to a large quantity of hexane to coagulate and purifythe resulting resin. After the addition of 150 g of propylene glycolmonomethyl ether to the purified resin, 300 g of methanol, 80 g oftriethylamine, and 15 g of water were added. The mixture was hydrolyzedfor eight hours while refluxing at a boiling point. After the reaction,the solvent and triethylamine were evaporated under reduced pressure.The resulting resin was dissolved in acetone and added dropwise to alarge quantity of water to coagulate the resin. The resulting whitepowder was filtered and dried overnight at 50° C. under reducedpressure.

The resin was found to have Mw and Mw/Mn of 11,500 and 1.6 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization molarratio of p-hydroxystyrene, t-butyl acrylate, p-t-butoxystyrene, and1-acryloyl-2-phenylbenzimidazole of the copolymer was 55:15:20:10. Thisresin is referred to as a “resin (A-6)”.

Synthesis Example 7

91 g of p-acetoxystyrene, 50 g of p-t-butoxystyrene, 14 g of 1-acryloylimidazole, 6 g of AIBN, and 1 g of t-dodecylmercaptan were dissolved in160 g of propylene glycol monomethyl ether. The mixture was polymerizedfor 16 hours at 70° C. in a nitrogen atmosphere. After polymerization,the reaction solution was added dropwise to a large quantity of hexaneto coagulate and purify the resulting resin. After the addition of 150 gof propylene glycol monomethyl ether to the resin, 300 g of methanol, 80g of triethylamine, and 15 g of water were added. The mixture washydrolyzed for 8 hours while refluxing at the boiling point. After thereaction, the solvent and triethylamine were evaporated under reducedpressure. The resulting resin was dissolved in acetone and addeddropwise to a large quantity of water to coagulate the resin. Theresulting white powder was filtered and dried overnight at 50° C. underreduced pressure.

The resin was found to have Mw and Mw/Mn of 16,000 and 1.7 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization ratioof p-hydroxystyrene, p-t-butoxystyrene, and 1-acryloyl imidazole of thecopolymer was 62:28:10. This resin is referred to as a “resin (A-7)”.

Synthesis Example 8

146 g of p-acetoxystyrene, 28 g of 1-acryloyl-2-phenylbenzimidazole, 6 gof AIBN, and 1 g of t-dodecylmercaptan were dissolved in 160 g ofpropylene glycol monomethyl ether. The mixture was polymerized for 16hours at 70° C. in a nitrogen atmosphere. After polymerization, thereaction solution was added dropwise to a large quantity of hexane tocoagulate and purify the resulting resin. After the addition of 150 g ofpropylene glycol monomethyl ether to the resin, 300 g of methanol, 80 gof triethylamine, and 15 g of water were added. The mixture washydrolyzed for 8 hours while refluxing at the boiling point. After thereaction, the solvent and triethylamine were evaporated under reducedpressure. The resulting resin was dissolved in acetone and addeddropwise to a large quantity of water to coagulate the resin. Theresulting white powder was filtered and dried overnight at 50° C. underreduced pressure.

The resin was found to have Mw and Mw/Mn of 16,000 and 1.7 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization ratioof p-hydroxystyrene and 1-acryloyl-2-phenylbenzimidazole was 90:10. Thisresin is referred to as a “resin (A-8)”.

Synthesis Example 9

101 g of p-acetoxystyrene, 5 g of styrene, 42 g of p-t-butoxystyrene, 6g of AIBN, and 1 g of t-dodecylmercaptan were dissolved in 160 g ofpropylene glycol monomethyl ether. The mixture was polymerized for 16hours at 70° C. in a nitrogen atmosphere. After polymerization, thereaction solution was added dropwise to a large quantity of hexane tocoagulate and purify the resulting resin. After the addition of 150 g ofpropylene glycol monomethyl ether to the resin, 300 g of methanol, 80 gof triethylamine, and 15 g of water were added. The mixture washydrolyzed for 8 hours while refluxing at the boiling point. After thereaction, the solvent and triethylamine were evaporated under reducedpressure. The resulting resin was dissolved in acetone and addeddropwise to a large quantity of water to coagulate the resin. Theresulting white powder was filtered and dried overnight at 50° C. underreduced pressure.

The resin was found to have Mw and Mw/Mn of 16,000 and 1.7 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization molarratio of p-hydroxystyrene, styrene, and p-t-butoxystyrene of thecopolymer was 72:5:23. This resin is referred to as a “resin (a-1)”.

Synthesis Example 10

100 g of p-acetoxystyrene, 25 g of t-butyl acrylate, 18 g of styrene, 6g of AIBN, and 1 g of t-dodecylmercaptan were dissolved in 230 g ofpropylene glycol monomethyl ether. The mixture was polymerized for 16hours at 70° C. in a nitrogen atmosphere. After polymerization, thereaction solution was added dropwise to a large quantity of hexane tocoagulate and purify the resulting resin. After the addition of 150 g ofpropylene glycol monomethyl ether to the resin, 300 g of methanol, 80 gof triethylamine, and 15 g of water were added. The mixture washydrolyzed for 8 hours while refluxing at the boiling point. After thereaction, the solvent and triethylamine were evaporated under reducedpressure. The resulting resin was dissolved in acetone and addeddropwise to a large quantity of water to coagulate the resin. Theresulting white powder was filtered and dried overnight at 50° C. underreduced pressure.

The resin was found to have Mw and Mw/Mn of 11,500 and 1.6 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization molarratio of p-hydroxystyrene, t-butyl acrylate, and styrene of thecopolymer was 61:19:20. This resin is referred to as a “resin (a-2)”.

Synthesis Example 11

125 g of p-acetoxystyrene, 20 g of t-butyl acrylate, 10 g of styrene, 8g of 2,5-dimethylhexane-2,5-diacrylate, 8 g of AIBN, and 6 g oft-dodecylmercaptan were dissolved in 170 g of propylene glycolmonomethyl ether. The mixture was polymerized for 16 hours whilemaintaining the reaction temperature at 70° C. in a nitrogen atmosphere.After polymerization, the reaction solution was added dropwise to alarge quantity of hexane to coagulate and purify the resulting resin.After the addition of 150 g of propylene glycol monomethyl ether to theresin, 300 g of methanol, 80 g of triethylamine, and 15 g of water wereadded. The mixture was hydrolyzed for 8 hours while refluxing at theboiling point. After the reaction, the solvent and triethylamine wereevaporated under reduced pressure. The resulting resin was dissolved inacetone and added dropwise to a large quantity of water to coagulate theresin. The resulting white powder was filtered and dried overnight at50° C. under reduced pressure.

The resin was found to have Mw and Mw/Mn of 40,000 and 2.6,respectively. The result of ¹³C-NMR analysis confirmed that thecopolymerization molar ratio of p-hydroxystyrene, t-butyl acrylate,styrene, and 2,5-dimethylhexane-2,5-diacrylate of the copolymer was72:10:15:3. This resin is referred to as a “resin (a-3)”.

Synthesis Example 12

140 g of p-acetoxystyrene, 50 g of p-t-butoxystyrene, 9 g of2,5-dimethylhexane-2,5-diacrylate, 8 g of AIBN, and 6 g oft-dodecylmercaptan were dissolved in 240 g of propylene glycolmonomethyl ether. The mixture was polymerized for 16 hours at 70° C. ina nitrogen atmosphere. After polymerization, the reaction solution wasadded dropwise to a large quantity of hexane to coagulate and purify theresulting resin. After the addition of 150 g of propylene glycolmonomethyl ether to the purified resin, 300 g of methanol, 100 g oftriethylamine, and 15 g of water were added. The mixture was hydrolyzedfor one hour while refluxing at a boiling point. After the reaction, thesolvent and triethylamine were evaporated under reduced pressure. Theresulting resin was dissolved in acetone and added dropwise to a largequantity of water to coagulate the resin. The resulting white powder wasfiltered and dried overnight at 50° C. under reduced pressure.

The resin was found to have Mw and Mw/Mn of 40,000 and 2.6 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization molarratio of p-hydroxystyrene, p-t-butoxystyrene, and2,5-hexanedimethanoldiacrylate of the copolymer was 67:30:3. This resinis referred to as a “resin (a-4)”.

Synthesis Example 13

176 g of p-t-butoxystyrene was anionically polymerized at −78° C. in 500ml of tetrahydrofuran using s-butyllithium as a catalyst. Afterpolymerization, the resulting resin solution was coagulated in methanolto obtain 150 g of white poly(p-t-butoxystyrene). Thepoly(p-t-butoxystyrene) was dissolved in 600 g of dioxane. After theaddition of diluted hydrochloric acid, the mixture was hydrolyzed at 70°C. for 2 hours. The reaction product was caused to coagulate in a largequantity of water to obtain a white resin. A step of dissolving theresulting resin in acetone and adding dropwise to a large quantity ofwater to coagulate the resin was repeated. The resulting white powderwas filtered and dried overnight at 50° C. under reduced pressure.

The Mw and Mw/Mn of this resin were 10,400 and 1.01, respectively.¹³C-NMR analysis confirmed that only part of t-butyl group in thepoly(p-t-butoxystyrene) had a hydrolyzed structure and the molar ratioof p-t-butoxystyrene and p-hydroxystyrene was 68:32. This resin isreferred to as a “resin (a-5)”.

Synthesis Example 14

7 g of di-t-butyl carbonate was added to a solution in which 12 g ofpoly(p-hydroxystyrene) and 5 g of triethylamine were dissolved in 50 gof dioxane while stirring. The mixture was stirred for 6 hours at roomtemperature. Oxalic acid was then added to neutralize triethylamine. Thereaction solution was dropped into a large quantity of water tocoagulate the resin. The coagulated resin was washed with purified waterseveral times. The resin was then filtered and dried at 50° C. overnightunder reduced pressure.

Mw and Mw/Mn of this resin were respectively 9,200 and 1.8. As a resultof ¹³C-NMR analysis, the resin was found to have a structure in which 30mol % of hydrogen atoms of a phenolic hydroxyl group inpoly(p-hydroxystyrene) was replaced by t-butoxycarbonyl groups. Thisresin is referred to as a “resin (a-6)”.

Synthesis Example 15

176 g of p-t-butoxystyrene was anionically polymerized at −78° C. in 500ml of tetrahydrofuran using s-butyllithium as a catalyst. Afterpolymerization, the resulting resin solution was coagulated in methanolto obtain 150 g of white poly(p-t-butoxystyrene). Thepoly(4-t-butoxystyrene) was dissolved in 600 g of dioxane. After theaddition of diluted hydrochloric acid, the mixture was hydrolyzed at 70°C. for 12 hours. The reaction product was caused to coagulate in a largequantity of water to obtain a white resin. A step of dissolving theresulting resin in acetone and adding dropwise to a large quantity ofwater to coagulate the resin was repeated. The resulting white powderwas filtered and dried overnight at 50° C. under reduced pressure.

The resin was confirmed to be poly(p-hydroxystyrene) having Mw of 11,400and Mw/Mn of 1.01.

Then, 24 g of this poly(p-hydroxystyrene) was dissolved in 100 g ofn-butyl acetate. Nitrogen gas was bubbled through the mixture for 30minutes. After the addition of 8 g of cyclohexyl vinyl ether and 1 g ofpyridinium p-toluenesulfonate as a catalyst, the mixture was allowed toreact at room temperature for 12 hours. The reaction solution wasdropped into a large quantity of 1 wt % ammonium aqueous solution tocoagulate the resin. The resin was filtered and dried overnight in avacuum drier at 50° C.

Mw and Mw/Mn of this resin were respectively 13,000 and 1.01. As aresult of ¹³C-NMR analysis, the resin was found to have a structure inwhich 23 mol % of hydrogen atoms of a phenolic hydroxyl group inpoly(p-hydroxystyrene) was replaced by 1-cyclohexyloxyethyl groups. Thisresin is referred to as a “resin (a-7)”.

Synthesis Example 16

24 g of poly(p-hydroxystyrene) with Mw of 12,000 was dissolved in 100 gof dioxane. Nitrogen gas was bubbled through the mixture for 30 minutes.After the addition of 3 g of ethyl vinyl ether and 3 g ofethyl-1-propenyl ether, and 1 g of pyridinium p-toluenesulfonate as acatalyst, the mixture was reacted for 12 hours at room temperature. Thereaction solution was dropped into a large quantity of 1 wt % ammoniumaqueous solution to coagulate the resin. The resin was filtered anddried overnight in a vacuum drier at 50° C.

Mw and Mw/Mn of this resin were respectively 15,000 and 1.6. As a resultof ¹³C-NMR analysis, the resin was found to have a structure in which 20mol % of hydrogen atoms of a phenolic hydroxyl group inpoly(p-hydroxystyrene) was replaced by 1-ethoxyethyl groups, and 15 mol% by 1-ethoxy propyl groups. This resin is referred to as a “resin(a-8)”.

Synthesis Example 17

25 g of a copolymer of p-hydroxystyrene and p-t-butoxystyrene wasdissolved in 100 g of n-butyl acetate. Nitrogen gas was bubbled throughthe mixture for 30 minutes. After the addition of 3.3 g of ethyl vinylether and 1 g of pyridinium p-toluenesulfonate as a catalyst, themixture was reacted at room temperature for 12 hours. The reactionsolution was dropped into a large quantity of 1 wt % ammonium aqueoussolution to coagulate the resin. The resin was filtered and driedovernight in a vacuum drier at 50° C.

Mw and Mw/Mn of this resin were respectively 13,000 and 1.01. As aresult of ¹³C-NMR analysis, the resin was found to have a structure inwhich 23 mol % of hydrogen atoms of a phenolic hydroxyl group inpoly(p-hydroxystyrene) was replaced by ethoxyethyl groups and 10 mol %by t-butyl groups. This resin is referred to as a “resin (a-10)”.

Synthesis Example 18

114 g of p-acetoxystyrene, 19 g of t-butylacrylate, 32 g ofp-t-butoxystyrene, 6 g of AIBN, and 1 g of t-dodecylmercaptan weredissolved in 230 g of propylene glycol monomethyl ether. The mixture waspolymerized for 16 hours at 70° C. in a nitrogen atmosphere. Afterpolymerization, the reaction solution was added dropwise to a largequantity of hexane to coagulate and purify the resulting resin. Afterthe addition of 150 g of propylene glycol monomethyl ether to thepurified resin, 300 g of methanol, 80 g of triethylamine, and 15 g ofwater were added. The mixture was hydrolyzed for eight hours whilerefluxing at a boiling point. After the reaction, the solvent andtriethylamine were evaporated under reduced pressure. The resultingresin was dissolved in acetone and added dropwise to a large quantity ofwater to coagulate the resin. The resulting white powder was filteredand dried overnight at 50° C. under reduced pressure.

The resin was found to have Mw and Mw/Mn of 11,500 and 1.6 respectively.The result of ¹³C-NMR analysis confirmed that the copolymerization molarratio of p-hydroxystyrene, t-butyl acrylate, and p-t-butoxystyrene ofthe copolymer was 65:15:20. This resin is referred to as a “resin(a-11)”.

Acid Generator (B)

-   B-1: Bis(4-t-butylphenyl)iodonium nonafluoro-n-butanesulfonate-   B-2: Bis(4-t-butylphenyl)iodonium 10-camphorsulfonate-   B-3: Bis(4-t-butylphenyl)iodoniumtrifluoromethane sulfonate-   B-4: n-Trifluoromethanesulfonyloxy-5-norbornene-2,3-dicarboxyimide-   B-5: Bis(cyclohexylsulfonyl)diazomethane-   B-6: Triphenylsulfoniumtrifluoromethanesulfonate-   B-7: N-(10-Camphorsulfonyloxy)succinimide    Crosslinking Agent (C)-   C-1: Dimethoxymethylurea (“MX290” manufactured by Sanwa Chemical    Co., Ltd.)-   C-2: Tetramethoxymethyl glycoluril (“CYMEL 1174” manufactured by    Mitsui° Cyanamid Co., Ltd.)    Acid Diffusion Control Agent-   D-1: Tri-n-octylamine-   D-2: Triethanolamine-   D-3: 2-Phenylpyridine-   D-4: N,N,N,N-Tetrakis(2-hydroxypropyl)ethylenediamine-   D-5: 1-t-Butylcarbonyloxy-2-phenylbenzimidazole    Alkali-Soluble Resin (E)-   E-1: Poly(p-hydroxystyrene) (Mw=7,500, Mw/Mn=1.1)-   E-2: p-Hydroxystyrene/styrene copolymer (copolymerization ratio:    8:2, Mw=4,500, Mw/Mn=11)    Other Additives-   F-1: Poly(p-hydroxystyrene) (Mw=3,000)-   F-2: 2,2-Bis(4-t-butoxyphenyl)propane-   F-3: 1-Adamantane carboxylic acid    Solvent-   G-1: Ethyl lactate-   G-2: Ethyl 3-ethoxypropionate-   G-3: Propylene glycol monoethyl ether    <Chemically Amplified Positive Tone Radiation Sensitive Resin    Composition>    Examples 1-40 and Comparative Examples 1-4

Components shown in Table 1 and Table 2 (part(s) indicates part(s) byweight) were mixed to prepare homogeneous solutions. The solutions werefiltered through a membrane filter with a pore diameter of 0.2 μm toprepare solution compositions. The solution compositions werespin-coated on a silicon wafer and pre-baked under the conditions shownin Tables 3 and 4 to form a resist films with a thickness of 0.5 μm.

The resist films were exposed under the conditions shown in Tables 3 and4 using a stepper “NSR2205 EX12B” (manufactured by Nikon Corp.,numerical aperture: 0.55) in Examples 1-17, Examples 21-38, andComparative Examples 1-3. In Examples 18-20, Examples 39-40, andComparative Example 4, the resist films were exposed using an electronbeam lithography system “HL700” (manufactured by Hitachi, Ltd.,acceleration voltage: 30 KeV) in which the acceleration voltage wasremodeled to 50 KeV. PEB was performed under the conditions shown inTables 3 and 4. The resist films were developed at 23° C. for 1 minuteby a paddle method using a 2.38 wt % tetramethyl ammonium hydroxideaqueous solution. The resist films were then washed with deionized waterand dried to form a resist pattern. The evaluation results of eachresist are shown in Tables 5 and 6. TABLE 1 Acid diffusion Acidgenerator Additives control agent Solvent (parts) Resin (parts) (parts)(parts) (parts) Example 1 B-1(2) a-1(95) F-3(0.1) D-4(0.2) G-1(200)B-3(2) A-1(5) Example 2 B-4(8) a-1(90), A-1(10) — D-5(0.15) G-1(200)Example 3 B-1(2) a-11(95), A-3(5) — D-5(0.2) G-1(160) B-3(0.5) G-3(40)Example 4 B-1(2) a-4(80), A-2(20) F-3(0.1) D-4(0.2) G-1(200) B-3(2)Example 5 B-4(6) a-1(60), A-1(40) — D-5(0.2) G-1(200) Example 6 B-1(2)a-2(90) — D-5(0.2) G-1(140) B-2(2) A-3(10) G-3(60) Example 7 B-4(4)a-3(80), A-3(20) — D-5(0.2) G-1(140) G-3(60) Example 8 B-4(6) a-4(80)F-3(0.1) D-2(0.2) G-1(140) B-2(2) A-3(20) G-3(60) Example 9 B-3(4)a-5(80), A-3(10) — D-5(0.1) G-1(200) Example 10 B-4(6) a-6(90), A-3(10)— D-5(0.1) G-1(200) Example 11 B-5(1) a-7(85) — D-2(0.2) G-2(200)E-1(10), A-3(5) Example 12 B-5(1) a-8(60) F-3(0.2) D-1(0.2) G-1(140)E-1(10), A-3(20) G-2(60) Example 13 B-4(8) a-1(90), A-4(10) — D-5(0.15)G-1(200) Example 14 B-6(3) a-10(70) F-3(0.2) D-1(0.1) G-1(140) E-2(20),A-3(10) D-2(0.1) G-2(60) Example 15 B-1(2) a-11(92) — D-5(0.2) G-1(200)B-3(0.5) E-1(5), A-2(3) Example 16 B-5(4) a-1(90), A-2(10) — D-5(0.2)G-1(200) Example 17 B-5(4) a-1(100), A-1(10) — D-5(0.15) G-1(200)Example 18 B-6(5) a-11(80), A-2(20) F-2(5) D-5(0.1) G-1(140) G-3(60)Example 19 B-6(5) a-4(90), A-3(10) — D-5(0.1) G-1(200) Example 20 B-6(5)a-1(100), A-1(10) — D-5(0.1) G-1(200)

TABLE 2 Acid diffusion Acid generator Additives control agent Solvent(parts) Resin (parts) (parts) (parts) (parts) Example 21 B-1(2) a-1(95)F-3(0.1) D-4(0.2) G-1(200) B-3(2) A-5(5) Example 22 B-4(8) a-1(90),A-5(10) — D-5(0.15) G-1(200) Example 23 B-1(2) a-11(95), A-7(5) —D-5(0.2) G-1(160) B-3(0.5) G-3(40) Example 24 B-1(2) a-4(80), A-6(20)F-3(0.1) D-4(0.2) G-1(200) B-3(2) Example 25 B-4(6) a-1(60), A-5(40) —D-5(0.2) G-1(200) Example 26 B-1(2) a-2(90) — D-5(0.2) G-1(140) B-2(2)A-7(10) G-3(60) Example 27 B-4(4) a-3(80), A-7(20) — D-5(0.2) G-1(140)G-3(60) Example 28 B-4(6) a-4(80) F-3(0.1) D-2(0.2) G-1(140) B-2(2)A-7(20) G-3(60) Example 29 B-3(4) a-5(80), A-7(10) — D-5(0.1) G-1(200)Example 30 B-4(6) a-6(90), A-7(10) — D-5(0.1) G-1(200) Example 31 B-5(1)a-7(85) — D-2(0.2) G-2(200) E-1(10), A-7(5) Example 32 B-5(1) a-8(60)F-3(0.2) D-1(0.2) G-1(140) E-1(10), A-7(20) G-2(60) Example 33 B-4(8)a-1(90), A-8(10) — D-5(0.15) G-1(200) Example 34 B-6(3) a-10(70)F-3(0.2) D-1(0.1) G-1(140) E-2(20), A-7(10) D-2(0.1) G-2(60) Example 35B-1(2) a-11(92) — D-5(0.2) G-1(200) B-3(0.5) E-1(5), A-6(3) Example 36B-5(4) a-1(90), A-6(10) — D-5(0.2) G-1(200) Example 37 B-5(4) a-1(100),A-5(10) — D-5(0.15) G-1(200) Example 38 B-4(5) a-1(90), — D-5(0.15)G-1(140) B-7(5) A-1 (10) G-3(60) B-2(1) Example 39 B-6(5) a-4(90),A-7(10) — D-5(0.1) G-1(200) Example 40 B-6(5) a-1(100), A-5(10) —D-5(0.1) G-1(200) Comparative B-1(2) a-4(100) F-3(0.1) D-4(0.2) G-1(200)Example 1 B-3(2) Comparative B-3(8) a-1(100) — D-5(0.2) G-1(200) Example2 Comparative B-4(6) a-11(100) — D-5(0.2) G-1(200) Example 3 B-2(2)Comparative B-6(3) a-1(100) — D-5(0.15) G-1(200) Example 4 B-4(4)

TABLE 3 Pre-bake Post-exposure bake Temper- Temper- ature Time atureTime (° C.) (S) Exposure source (° C.) (S) Example 1 130 60 KrF excimerlaser 130 60 Example 2 130 60 KrF excimer laser 130 60 Example 3 130 60KrF excimer laser 130 60 Example 4 130 60 KrF excimer laser 130 60Example 5 130 60 KrF excimer laser 130 60 Example 6 110 60 KrF excimerlaser 130 60 Example 7 110 60 KrF excimer laser 130 60 Example 8 130 60KrF excimer laser 130 60 Example 9 110 60 KrF excimer laser 100 60Example 10 90 60 KrF excimer laser 100 60 Example 11 90 60 KrF excimerlaser 100 60 Example 12 90 60 KrF excimer laser 100 60 Example 13 130 60KrF excimer laser 130 60 Example 14 90 60 KrF excimer laser 100 60Example 15 130 60 KrF excimer laser 130 60 Example 16 130 60 KrF excimerlaser 130 60 Example 17 130 60 KrF excimer laser 130 60 Example 18 11060 Electron beam 130 60 Example 19 110 60 Electron beam 130 60 Example20 110 60 Electron beam 130 60

TABLE 4 Pre-bake Post-exposure bake Temper- Temper- ature Time atureTime (° C.) (S) Exposure source (° C.) (S) Example 21 130 60 KrF excimerlaser 130 60 Example 22 130 60 KrF excimer laser 130 60 Example 23 13060 KrF excimer laser 130 60 Example 24 130 60 KrF excimer laser 130 60Example 25 130 60 KrF excimer laser 130 60 Example 26 110 60 KrF excimerlaser 130 60 Example 27 110 60 KrF excimer laser 130 60 Example 28 13060 KrF excimer laser 130 60 Example 29 110 60 KrF excimer laser 100 60Example 30 90 60 KrF excimer laser 100 60 Example 31 90 60 KrF excimerlaser 100 60 Example 32 90 60 KrF excimer laser 100 60 Example 33 130 60KrF excimer laser 130 60 Example 34 90 60 KrF excimer laser 100 60Example 35 130 60 KrF excimer laser 130 60 Example 36 130 60 KrF excimerlaser 130 60 Example 37 130 60 KrF excimer laser 130 60 Example 38 13060 KrF excimer laser 130 60 Example 39 110 60 Electron beam 130 60Example 40 110 60 Electron beam 130 60 Comparative 130 60 KrF excimerlaser 130 60 Example 1 Comparative 130 60 KrF excimer laser 130 60Example 2 Comparative 130 60 KrF excimer laser 130 60 Example 3Comparative 130 60 Electron beam 130 60 Example 4

TABLE 5 Sensitivity Resolution Iso-dense Storage (mJ/cm²) (μm) PED biasstability Example 1 25 0.20 Good Good Good Example 2 22 0.18 Good GoodGood Example 3 24 0.19 Good Good Good Example 4 23 0.18 Good Good GoodExample 5 23 0.17 Good Good Good Example 6 25 0.19 Good Good GoodExample 7 24 0.20 Good Good Good Example 8 24 0.20 Good Good GoodExample 9 23 0.20 Good Good Good Example 10 26 0.20 Good Good GoodExample 11 23 0.20 Good Good Good Example 12 22 0.20 Good Good GoodExample 13 22 0.21 Good Good Good Example 14 23 0.20 Good Good GoodExample 15 25 0.18 Good Good Good Example 16 25 0.19 Good Good GoodExample 17 24 0.17 Good Good Good Example 18 4 uC 0.17 Good Good GoodExample 19 5 uC 0.17 Good Good Good Example 20 3 uC 0.18 Good Good Good

TABLE 6 Sensitivity Resolution Iso-dense Storage (mJ/cm²) (μm) PED biasstability Example 21 25 0.19 Good Good Good Example 22 22 0.18 Good GoodGood Example 23 24 0.18 Good Good Good Example 24 23 0.18 Good Good GoodExample 25 23 0.17 Good Good Good Example 26 25 0.19 Good Good GoodExample 27 24 0.20 Good Good Good Example 28 24 0.20 Good Good GoodExample 29 23 0.20 Good Good Good Example 30 26 0.19 Good Good GoodExample 31 23 0.20 Good Good Good Example 32 22 0.20 Good Good GoodExample 33 22 0.19 Good Good Good Example 34 23 0.19 Good Good GoodExample 35 25 0.17 Good Good Good Example 36 25 0.18 Good Good GoodExample 37 24 0.18 Good Good Good Example 38 30 0.17 Good Good GoodExample 39 5 uC 0.14 Good Good Good Example 40 3 uC 0.14 Good Good GoodComparative 34 0.22 Good Bad Good Example 1 Comparative 27 0.20 Bad BadGood Example 2 Comparative 26 0.22 Bad Bad Bad Example 3 Comparative 5uC 0.22 Bad Good Bad Example 4

Measurement of Mw and Mn in the above Examples 1-40, ComparativeExamples 1-4 and the following Examples 21-23 and Comparative Example 5,and evaluation of each composition were carried out as follows.

Mw and Mn

Mw was measured by gel permeation chromatography (GPC) using GPC columns(manufactured by Tosoh Corp., G2000HXL×2, G3000HXL×1, G4000HXL×1) underthe following conditions. Flow rate: 1.0 ml/minute, eluate:tetrahydrofuran, column temperature: 40° C., standard referencematerial: monodispersed polystyrene

Sensitivity

Sensitivity was evaluated based on an optimum exposure dose which is adose capable of forming a 1:1 line and space pattern (1L1S) with a linewidth of 0.22 μm, when a resist film formed on a silicon wafer isexposed to light, immediately followed by baking, alkali development,washing with water, and drying.

Resolution (1L1S)

A minimum dimension of line-and-space patterns (1L1S) resolved at anoptimum dose at which a 1:1 1L1S with a line width of 0.25 μm is formedis taken as a standard for resolution.

Iso-Dense Bias

An iso-dense bias was determined by subtracting 0.18 μm from a 1L5Spattern size when a resist is exposed to an optimum dose, which is adose capable of forming a 1:1 line width from a line-and-space (1L1S)pattern with a designed line width of 0.18 μm. A resist not forming a1L5S pattern with the optimum dose is judged “incapable of formingpatterns”.

PED Stability

A resist, exposed to radiation at a dose equivalent to an optimum dosewhen a resist is baked and developed immediately after exposure, wasplaced for two hours in a chamber in which an ammonia concentration iscontrolled at 5 ppb, followed by post exposure baking to form aline-and-space (1L1S) pattern with a designed line width of 0.18 μm. PEDstability was judged to be “Excellent” when the line width at the top ofthe pattern (L_(top)) satisfies an inequality0.85×0.18<L_(top)<1.1×0.18, otherwise judged to be “Bad”. A judgment of“No pattern separation” was given when no line-and-space (1L1S) patternwith a designed line width of 0.18 μm was formed.

Storage Stability

Storage stability was judged to be “Excellent” when sensitivity within72 hours after preparation (a) and the sample sensitivity after storingfor 3 months or longer at 23° C. (b) satisfy an inequality−0.1<(b−a)/a<0.1, otherwise judged to be “Bad”.

<Chemically Amplified Negative Tone Radiation Sensitive ResinComposition>

Examples 41-42 and Comparative Example 5

Components shown in Table 7 (part(s) indicates part(s) by weight) weremixed to prepare homogeneous solutions. The solutions were filteredthrough a membrane filter with a pore diameter of 0.2 μm to preparesolution compositions. The solution composition was spin-coated on asilicon wafer. PB was then performed under the conditions shown in Table8 to form a resist coating with a thickness of 0.5 μm.

The resist films were exposed under the conditions shown in Table 8using a stepper “NSR2205 EX12B” (manufactured by Nikon Corp., numericalaperture: 0.55) and baked (PEB) under the conditions shown in Table 8.The resist films were developed at 23° C. for 1 minute by a paddlemethod using a 2.38 wt % tetramethyl ammonium hydroxide aqueoussolution. The resist films were then washed with deionized water anddried to form a resist pattern. The results of the evaluation of eachresist are shown in Table 9. TABLE 7 Acid Added Acid diffusion generatorResin Crosslinking control agent Solvent (parts) (parts) agent (parts)(parts) (parts) Example 41 B-6(2) c-2(90) C-1(7) D-1(0.5) G-1(600)A-1(10) Example 42 B-6(2) c-1(90) C-2(7) D-1(0.5) G-1(600) A-3(10)Comparative B-6(2) c-2(100) C-1(7) D-1(0.5) G-1(600) Example 5

TABLE 8 Pre-bake Post-exposure bake Temper- Temper- ature Time atureTime (° C.) (S) Exposure source (° C.) (S) Example 41 90 60 KrF excimerlaser 110 60 Example 42 90 60 KrF excimer laser 110 60 Comparative 90 60KrF excimer laser 110 60 Example 5

TABLE 9 Sensitivity Resolution Iso-dense Storage (mJ/cm²) (

m) PED bias stability Example 41 30 0.20 Good Good Good Example 42 290.20 Good Good Good Comparative 30 0.21 Bad Bad Good Example 5<Synthesis of Component (A3)>Synthesis Example 19

A 1 l three necked egg plant flask was charged with 396.2 g (4 mol) ofN,N-dimethylacrylamide, followed by nitrogen gas purge. A 500 mldripping funnel was charged with 318 ml (4 mol) of cyclopentadiene undernitrogen gas atmosphere. The flask was heated at 50° C. andcyclopentadiene was slowly added dropwise from the dripping funnel at arate of 2 ml/min. After the addition, the mixture was allowed to standfor 5 hours while heating at 50° C. The conversion rate was determinedby gas chromatography to confirm that the yield of the target compoundwas 85 mol %. The reaction solution was purified by vacuum distillationat 87° C. and 0.8 mmHg to obtainN,N-dimethylbicyclo[2.2.1]hepto-2-ene-5-carboxylic acid amide at a yieldof 70 mol %. This compound is referred to as a “Norbornene derivative(I-1)”.

Synthesis Example 20

4.9 g of the norbornene derivative (I-1), 13.0 g of a (meth)acrylic acidderivative shown by the following formula (12) (hereinafter referred toas “(meth)acrylic acid derivative {circle over (1)}”), 20.6 g of anorbornene derivative shown by the following formula (13) (hereinafterreferred to as “norbornene derivative {circle over (2)}”), and 11.5 g ofmaleic anhydride were dissolved in 50 g of tetrahydrofuran to obtain ahomogeneous solution. After injection of nitrogen for 30 minutes, 2.9 gof azobisisobutyronitrile was added as an initiator. The mixture washeated to 65° C. and stirred for 6 hours at this temperature. After thereaction, the reaction solution was cooled to room temperature anddiluted with 50 g of tetrahydrofuran. The diluted solution was pouredinto 1,000 ml of n-hexane to cause the resin to precipitate, therebyobtaining 35 g (yield: 70 wt %) of white resin powder.

This resin was confirmed to be a copolymer having an Mw of 4,300,consisting of norbornene derivative (I-1), (meth)acrylic acid derivative{circle over (1)}, norbornene derivative {circle over (2)}, and maleicanhydride at a proportion of 10 mol %, 20 mol %, 30 mol %, and 40 mol %respectively. This resin is referred to as a “resin (A-9)”.

Synthesis Example 21

2.9 g of N,N-dimethylacrylamide, 13.0 g of (meth)acrylic acid derivative{circle over (1)}, 24.0 g norbornene derivative {circle over (2)}, and10.1 g of maleic anhydride were dissolved in 50 g of tetrahydrofuran toobtain a homogeneous solution. After injection of nitrogen for 30minutes, 2.9 g of azobisisobutyronitrile was added as an initiator. Themixture was heated to 65° C. and stirred for 6 hours at thistemperature. After the reaction, the reaction solution was cooled toroom temperature and diluted with 50 g of tetrahydrofuran. The dilutedsolution was poured into 1,000 ml of n-hexane to cause the resin toprecipitate, thereby obtaining 37 g (yield: 74 wt %) of white resinpowder.

This resin was confirmed to be a copolymer having an Mw of 4,900,consisting of recurring units derived from N,N-dimethylacrylamide,(meth)acrylic acid derivative {circle over (1)}, norbornene derivative{circle over (2)}, and maleic anhydride at a proportion of 10 mol %, 20mol %, 35 mol %, and 35 mol % respectively. This resin is referred to asa “resin (A-10)”.

Synthesis Example 22

4.5 g of the norbornene derivative (I-1), 12.2 g of (meth)acrylic acidderivative {circle over (1)}, 22.6 g of a norbornene derivative shown bythe following formula (14) (hereinafter referred to as “norbornenederivative {circle over (3)}”), and 10.7 g of maleic anhydride weredissolved in 50 g of tetrahydrofuran to obtain a homogeneous solution.After injection of nitrogen for 30 minutes, 2.7 g ofazobisisobutyronitrile was added as an initiator. The mixture was heatedto 65° C. and stirred for 6 hours at this temperature. After thereaction, the reaction solution was cooled to room temperature anddiluted with 50 g of tetrahydrofuran. The diluted solution was pouredinto 1,000 ml of n-hexane to cause the resin to precipitate, therebyobtaining 36 g (yield: 72 wt %) of white resin powder.

This resin was confirmed to be a copolymer having an Mw of 4,500,consisting of the recurring units derived from the norbornene derivative(I-1), (meth)acrylic acid derivative {circle over (1)}, norbornenederivative {circle over (3)}, and maleic anhydride at a proportion of 10mol %, 20 mol %, 30 mol %, and 40 mol % respectively. This resin isreferred to as a “resin (A-11)”.

Synthesis Example 23

2.7 g of N,N-dimethylacrylamide, 12.0 g of (meth)acrylic acid derivative{circle over (1)}, 26.0 g norbornene derivative {circle over (3)}, and9.3 g of maleic anhydride were dissolved in 50 g of tetrahydrofuran toobtain a homogeneous solution. After injection of nitrogen for 30minutes, 2.7 g of azobisisobutyronitrile was added as an initiator. Themixture was heated to 65° C. and stirred for 6 hours at thistemperature. After the reaction, the reaction solution was cooled toroom temperature and diluted with 50 g of tetrahydrofuran. The dilutedsolution was poured into 1,000 ml of n-hexane to cause the resin toprecipitate, thereby obtaining 37 g (yield: 74 wt %) of white resinpowder.

This resin was confirmed to be a copolymer having an Mw of 4,500,consisting of the recurring units derived from N,N-dimethylacrylamide,(meth)acrylic acid derivative {circle over (1)}, norbornene derivative{circle over (3)}, and maleic anhydride at a proportion of 10 mol %, 20mol %, 35 mol %, and 35 mol % respectively. This resin is referred to asa “resin (A-12)”.

Synthesis Example 24

2.4 g of N,N-dimethylacrylamide, 18.6 g of 2-methyl-2-adamantylmethacrylate, 28.0 g of a compound shown by the following formula (15),and 1.0 g of methacrylic acid were dissolved in 50 g of tetrahydrofuranto obtain a homogeneous solution. After injection of nitrogen for 30minutes, 2.4 g of azobisisobutyronitrile was added as an initiator. Themixture was heated to 65° C. and stirred for 6 hours at thistemperature. After the reaction, the reaction solution was cooled toroom temperature and diluted with 50 g of tetrahydrofuran. The dilutedsolution was poured into 1,000 ml of n-hexane to cause the resin toprecipitate, thereby obtaining 38 g (yield: 76 wt %) of white resinpowder.

This resin was confirmed to be a copolymer having an Mw of 11,900,consisting of the recurring units derived from N,N-dimethylacrylamide,2-methyl-2-adamantyl methacrylate, the compound shown by the formula(15), and methacrylic acid at a proportion of 10 mol %, 35 mol %, 50 mol%, and 5 mol % respectively. This resin is referred to as a “resin(A-13)”.

Synthesis Example 25

2.5 g of N,N-dimethylacrylamide, 17.1 g of 1-ethylcyclohexylmethacrylate, 29.3 g of a compound shown by the above formula (15), and1.1 g of methacrylic acid were dissolved in 50 g of tetrahydrofuran toobtain a homogeneous solution. After injection of nitrogen for 30minutes, 2.4 g of azobisisobutyronitrile was added as an initiator. Themixture was heated to 65° C. and stirred for 6 hours at thistemperature. After the reaction, the reaction solution was cooled toroom temperature and diluted with 50 g of tetrahydrofuran. The dilutedsolution was poured into 1,000 ml of n-hexane to cause the resin toprecipitate, thereby obtaining 39 g (yield: 78 wt %) of white resinpowder.

This resin was confirmed to be a copolymer having an Mw of 10,900,consisting of the recurring units derived from N,N-dimethylacrylamide,1-ethylcyclohexyl methacrylate, the compound shown by the formula (15),and methacrylic acid at a proportion of 10 mol %, 35 mol %, 50 mol %,and 5 mol % respectively. This resin is referred to as a “resin (A-14)”.

Synthesis Example 26

12.5 g of (meth)acrylic acid derivative {circle over (1)}, 26.4 gnorbornene derivative {circle over (2)}, and 11.1 g of maleic anhydridewere dissolved in 50 g of tetrahydrofuran to obtain a homogeneoussolution. After injection of nitrogen for 30 minutes, 2.8 g ofazobisisobutyronitrile was added as an initiator. The mixture was heatedto 65° C. and stirred for 6 hours at this temperature. After thereaction, the reaction solution was cooled to room temperature anddiluted with 50 g of tetrahydrofuran. The diluted solution was pouredinto 1,000 ml of n-hexane to cause the resin to precipitate, therebyobtaining 33 g (yield: 67 wt %) of white resin powder.

This resin was confirmed to be a copolymer having an Mw of 4,800,consisting of the recurring units derived from the (meth)acrylic acidderivative {circle over (1)}, norbornene derivative {circle over (2)},and maleic anhydride at a proportion of 20 mol %, 40 mol %, and 40 mol %respectively. This resin is referred to as a “resin (a-12)”.

Synthesis Example 27

11.5 g of (meth)acrylic acid derivative {circle over (1)}, 28.4 gnorbornene derivative {circle over (2)}, and 11.1 g of maleic anhydridewere dissolved in 50 g of tetrahydrofuran to obtain a homogeneoussolution. After injection of nitrogen for 30 minutes, 2.5 g ofazobisisobutyronitrile was added as an initiator. The mixture was heatedto 65° C. and stirred for 6 hours at this temperature. After thereaction, the reaction solution was cooled to room temperature anddiluted with 50 g of tetrahydrofuran. The diluted solution was pouredinto 1,000 ml of n-hexane to cause the resin to precipitate, therebyobtaining 33 g (yield: 66 wt %) of white resin powder.

This resin was confirmed to be a copolymer having an Mw of 4,200,consisting of the recurring units derived from (meth)acrylic acidderivative {circle over (1)}, norbornene derivative {circle over (2)},and maleic anhydride at a proportion of 20 mol %, 40 mol %, and 40 mol %respectively. This resin is referred to as a “resin (a-13)”.

Synthesis Example 28

20.0 g of 2-methyl-2-adamantyl methacrylate, 29.0 g of a compound shownby the above formula (15), and 1.0 g of methacrylic acid were dissolvedin 50 g of tetrahydrofuran to obtain a homogeneous solution. Afterinjection of nitrogen for 30 minutes, 2.2 g of azobisisobutyronitrilewas added as an initiator. The mixture was heated to 65° C. and stirredfor 6 hours at this temperature. After the reaction, the reactionsolution was cooled to room temperature and diluted with 50 g oftetrahydrofuran. The diluted solution was poured into 1,000 ml ofn-hexane to cause the resin to precipitate, thereby obtaining 39 g(yield: 78 wt %) of white resin powder.

This resin was confirmed to be a copolymer having an Mw of 11,500,consisting of the recurring units derived from 2-methyl-2-adamantylmethacrylate, the compound shown by the formula (15), and methacrylicacid at a proportion of 40 mol %, 55 mol %, and 5 mol % respectively.This resin is referred to as a “resin (a-14)”.

Synthesis Example 29

30.4 g of a compound shown by the above formula (15), 1.0 g ofmethacrylic acid, and 18.6 g of 1-ethylcyclohexyl methacrylate weredissolved in 50 g of tetrahydrofuran to obtain a homogeneous solution.After injection of nitrogen for 30 minutes, 2.2 g ofazobisisobutyronitrile was added as an initiator. The mixture was heatedat 65° C. and stirred for 6 hours at this temperature. After thereaction, the reaction solution was cooled to room temperature anddiluted with 50 g of tetrahydrofuran. The diluted solution was pouredinto 1,000 ml of n-hexane to cause the resin to precipitate, therebyobtaining 40 g (yield: 80 wt %) of white resin powder.

This resin was confirmed to be a copolymer having an Mw of 11,000,consisting of recurring units derived from the compound shown by theformula (15), methacrylic acid, 1-ethylcyclohexyl methacrylate at aproportion of 55 mol %, 5 mol %, and 40 mol % respectively. This resinis referred to as a “resin (a-15)”.

Measurement and evaluation in the following examples and comparativeexamples were carried out as follows.

Mw:

Mw was measured by gel permeation chromatography (GPC) using GPC columns(manufactured by Tosoh Corp., G2000HXL×2, G3000HXL×1, G4000HXL×1) underthe following conditions. Flow rate: 1.0 ml/minute, eluate:tetrahydrofuran, column temperature: 40° C., standard referencematerial: monodispersed polystyrene

Radiation Transmittance:

A solution composition was applied to a quartz plate and the coating waspost-baked on a hot plate at 90° C. for 60 seconds to obtain a resistfilm with a thickness of 1 μm. Radiation transmittance of the resistfilm was calculated from absorbance at a wavelength of 193 nm and wasadopted as a standard for transparency in the deep UV ray region.

Sensitivity:

A solution composition was applied to a silicon wafer with a 520 Åthickness Deep UV30 film (manufactured by Brewer Science Corp.) coatedon the surface by spin coating and post-baked on a hot plate under theconditions shown in Table 2 to obtain a resist coating with a thicknessof 0.34 μm. The coating was exposed to radiation through a mask patternusing an ArF excimer laser exposure apparatus (manufactured by NikonCorp., lens numerical aperture: 0.55, wavelength: 193 nm). Afterperforming PEB under the conditions shown in Table 2, the resist filmswere developed in a 38 wt % tetramethylammonium hydroxide aqueoussolution, developed at 25° C. for 1 minute, washed with water, and driedto form a positive-tone resist pattern. An optimum dose at which aline-and-space (1L1S) pattern with a line width of 0.16 μm was formedwas taken as sensitivity.

Resolution:

The minimum dimension of a resist pattern resolved at the optimum dosewas taken as the resolution of the resist coating.

Line Width Fluctuation Value:

In the same manner as in the measurement of sensitivity described above,line-and-space patterns (1L1S) and (1L10S) were formed by exposing aresist sample with a light at the optimum optimum dose at which a one toone line-and-space pattern (1L1S) with a line width of 0.16 μm can beformed. The line width fluctuation value due to fluctuation of the spacewidth was determined by measuring the difference between the line widthfor the line-and-space pattern (1L1S) and the line width for theline-and-space pattern (1L10S) by a scanning electron microscope.

Pattern Configuration:

The dimensions of the lower side L₁ and the upper side L₂ of therectangular cross-section of a line and space pattern (1L1S) with a linewidth of 0.16 μm were measured using a scanning electron microscope. Apattern shape which satisfied a formula “0.85=L₂/L₁=1” and was straightwith no extended skirt was evaluated as “Good”, and otherwise evaluatedas “Bad”.

Examples 43-48

Each composition solution having components shown in Table 10 wasevaluated. The evaluation conditions are shown in Table 11, and theresults are shown in Table 12. Components other than the polymers (A-9)to (A-14), and polymers (a-12) to (a-15) shown in Table 10 are asfollows.

Acid Generator (B)

-   B-8:    1-(3,5-dimethyl-4-hydroxyphenyl)tetrahydrothiophenium-perfluoro-n-octanesulfonate-   B-9: Bis(4-t-butylphenyl)iodonium perfluoro-n-octanesulfonate-   B-10:    Nonafluoro-n-butanesulfonylbicyclo[2.2.1]hepto-5-ene-2,3-dicarboxyimide-   B-11:    Perfluoro-n-octanesulfonylbicyclo[2.2.1]hepto-5-ene-2,3-dicarboxyimide    Acid Diffusion Control Agent-   D-5: N-t-butoxycarbonyl-2-phenylbenzimidazole-   D-6: N-t-butoxycarbonyldicyclohexylamine    Other Additives-   F-4: Di-t-butyl 1,3-adamantanedicarboxylate-   F-5: 2,5-Dimethyl-2,5-di(adamantylcarbonyloxy)hexane-   F-6: 2-Methyl-2-adamantylcarbonyloxyadamantane    Solvent-   G-4: 2-Heptanone-   G-5: Cyclohexanone

G-6: Propylene glycol monoethyl ether acetate TABLE 10 Acid Aciddiffusion Other Copolymer Generator control agent additives SolventExample 43 A-9(9.0) B-8(2.0) D-5(0.10) F-5(10) G-6(530) a-12(81.0)B-10(1.5) Example 44 A-10(9.0) B-9(2.0) D-5(0.01) F-6(10) G-4(430)a-12(81.0) B-11(2.0) D-6(0.09) G-5(100) Example 45 A-11(9.0) B-8(2.0)D-5(0.02) F-5(10) G-4(430) a-12(81.0) B-10(1.5) D-6(0.08) G-5(100)Example 46 A-12(9.0) B-9(2.0) D-5(0.10) F-4(10) G-6(530) a-13(81.0)B-11(2.0) Example 47 A-13(9.0) B-8(2.0) D-5(0.06) F-4(3) G-4(430)a-14(81.0) B-10(1.5) G-5(100) Example 48 A-14(9.0) B-9(2.0) D-5(0.06)F-4(3) G-4(430) a-15(81.0) B-11(2.0) G-5(100)

TABLE 11 PB PEB Resist film Substrate Temperature Temperature thicknessform (° C.) Time (S) (° C.) Time (S) Example 43 0.34 ARC 130 90 120 90Example 44 0.34 ARC 130 90 110 90 Example 45 0.34 ARC 130 90 120 90Example 46 0.34 ARC 130 90 120 90 Example 47 0.34 ARC 130 90 130 90Example 48 0.34 ARC 130 90 120 90

TABLE 12 Line width Radiation Resolu- fluctuation Pattern transmittanceSensitivity tion value configura- (193 nm, %) (J/m²) (μm) (nm) tionExample 43 70 300 0.14 10 Good Example 44 74 260 0.14 5 Good Example 4569 320 0.14 9 Good Example 46 68 290 0.14 11 Good Example 47 70 300 0.149 Good Example 48 72 270 0.14 13 Good

The radiation-sensitive resin composition of the present inventionexhibits excellent resolution and pattern configuration, particularlyexcellent narrow space processing performance, is affected by PED onlyto a minimal extent, exhibits a minimal iso-dense bias, and capable offorming fine patterns at a high precision and in a stable manner. Inaddition, the radiation-sensitive resin composition effectively respondsto various radiations such as ultraviolet rays, deep ultraviolet rays,X-rays, electron beams, and the like. Therefore, the radiation-sensitiveresin composition of the present invention is suitable as achemically-amplified positive resist used for fabricating semiconductordevices, which will become more and more minute.

1. A positive-tone radiation-sensitive resin composition comprising (A1)a copolymer which comprises a recurring unit shown by the followingformula (1) and/or a recurring unit shown by the following formula (2),and a recurring unit shown by the following formula (3-1), and (B) aphotoacid generator,

wherein R¹ represents a hydrogen atom or a methyl group;

wherein R¹ represents a hydrogen atom or a methyl group, and R²represents a tertiary alkyl group having 4-10 carbon atoms;

wherein R¹ represents a hydrogen atom or a methyl group, R³ and R⁴individually represent a hydrogen atom, a substituted or unsubstitutedalkyl group having 1-12 carbon atoms, a substituted or unsubstitutedaromatic group having 6-15 carbon atoms, or a substituted orunsubstituted alkoxyl group having 1-12 carbon atoms, or R³ and R⁴ mayform, in combination and together with the nitrogen atom with which theR³ and R⁴ groups bond, a cyclic structure having 3-15 carbon atoms,provided that R³ and R₄ are not a hydrogen atom at the same time.
 2. Thecomposition according to claim 1, wherein the recurring unit shown bythe formula (3-1) is a unit derived from N,N-dimethyl(meth)acrylamide.3. The composition according to claim 1, wherein the recurring unitshown by the formula (3-1) is a unit derived from1-(meth)acryloyl-2-phenylbenzimidazole.
 4. The composition according toclaim 1, wherein the recurring unit shown by the formula (3-1) is a unitderived from 1-(meth)acryloyl imidazole.
 5. The composition according toclaim 1, wherein the component (B) is at least one compound selectedfrom the group consisting of onium salt compounds and sulfonimidecompounds.
 6. The composition according to claim 1, wherein thecopolymer (A1) comprises a recurring unit derived from a styrenecompound in addition to the recurring units (1), (2), and (3-1). 7-8.(canceled)
 9. A radiation-sensitive resin composition comprising: (A) aresin which is insoluble or scarcely soluble in alkali and becomesalkali soluble by the action of an acid, the resin comprising therecurring unit (A3-1) of the following formula (3-2), and (B) aphotoacid generator,

R³ and R⁴ individually represent a hydrogen atom, a substituted orunsubstituted alkyl group having 1-12 carbon atoms, a substituted orunsubstituted alkoxyl group having 1-12 carbon atoms, or a substitutedor unsubstituted alkoxycarbonyl group having 2-13 carbon atoms, orR^(3′) and R⁴ may form, in combination and together with the nitrogenatom with which the R^(3′) and R^(4′) groups bond, a cyclic structurehaving 3-15 carbon atoms, and n is an integer of 0-3.
 10. Aradiation-sensitive resin composition comprising: (A) a resin which isinsoluble or scarcely soluble in alkali and becomes alkali soluble bythe action of an acid, the resin comprising the recurring unit (A3-2) ofthe following formula (3-1′) and having an alicyclic structure, and (B)a photoacid generator,

wherein R¹ represents a hydrogen atom or a methyl group, R_(3″) andR_(4″) individually represent a hydrogen atom, a substituted orunsubstituted alkyl group having 1-12 carbon atoms, a substituted orunsubstituted alkoxyl group having 1-12 carbon atoms, or a substitutedor unsubstituted alkoxycarbonyl group having 2-13 carbon atoms, orR_(3″) and R_(4″) may form, in combination and together with thenitrogen atom with which the R_(3″) and R_(4″) groups bond, a cyclicstructure having 3-10 carbon atoms.
 11. A radiation-sensitive resincomposition comprising: (A) a resin which is insoluble or scarcelysoluble in alkali and becomes alkali soluble by the action of an acid,the resin comprising the recurring unit (3-2) and/or the recurring unit(3-1′) of the following formula, and the recurring unit (1) and/or therecurring unit (ii) of the following formula, and (B) a photoacidgenerator,

wherein R¹, R^(3′), R^(4′), R^(3″), and R^(4″) are the same as definedin claims 3 or 4; R⁵ individually represents a linear or branched alkylgroup having 1-4 carbon atoms or a monovalent alicyclic hydrocarbongroup having 4-20 carbon atoms or derivatives thereof, provided that atleast one R⁵ is a linear groups form, in combination and together withthe carbon atoms to which the two R⁵ groups bond, a divalent alicyclichydrocarbon group having 4-20 carbon atoms or derivatives thereof, withthe remaining R⁵ groups being a linear or branched alkyl group having1-4 carbon atoms; R⁶ individually represents a linear or branched alkylgroup having 1-4 carbon atoms or monovalent alicyclic hydrocarbon grouphaving 4-20 carbon atoms or derivatives thereof, provided that at leastone R⁶ is a linear or branched alkyl group having 1-4 carbon atoms, orany two R⁶groups form, in combination and together with the carbon atomsto which the two R⁶ groups bond, a divalent alicyclic hydrocarbon grouphaving 4-20 carbon atoms or derivatives thereof, with the remaining R⁵groups being a linear or branched alkyl group having 1-4 carbon atoms;and m and n are an integer of 0-3.
 12. The composition according toclaim 11, wherein the resin (A) comprises the recurring unit (3-1′) andthe recurring unit (ii).
 13. The composition according to claim 12,wherein the resin (A) further comprises a recurring unit derived from acompound shown by the following formula (9),


14. The composition according to claim 11, further comprising anitrogen-containing organic compound as an acid diffusion controller.15. The positive-tone radiation-sensitive resin composition of claim 1,wherein the copolymer (A1) comprises a recurring unit shown by theformula (2).
 16. The positive-tone radiation-sensitive resin compositionof claim 1, wherein the copolymer (A1) comprises a recurring unit shownby the formula (2) and a recurring unit shown by the formula (1). 17.The positive-tone radiation-sensitive resin composition according toclaim 1 wherein the composition further comprises one or more othercopolymers.
 18. The positive-tone radiation-sensitive resin compositionaccording to claim 17, wherein the one or more other copolymers comprisethe recurring unit (1).
 19. The positive-tone radiation-sensitive resincomposition according to claim 18, wherein the one or more othercopolymers comprise the recurring unit (2).